Remove unused Babel transformations (#6811)

The `stage-0` Babel preset has been replaced with the specific Babel
plugins that we depend upon. We don't use most of `stage-0`, so this
allowed us to remove many unnecessary transformations. We had to remove
this preset soon anyway, because all of the stage presets are
deprecated in Babel 7.

The `stage-0` preset consisted of these plugins:
```
"transform-do-expressions"
"transform-function-bind"
"transform-class-constructor-call"
"transform-export-extensions"
"transform-class-properties"
"transform-decorators"
"syntax-dynamic-import"
"syntax-trailing-function-commas"
"transform-async-generator-functions"
"transform-async-to-generator"
"transform-exponentiation-operator"
"transform-object-rest-spread"
```

Of that list, only 'transform-class-properties', 'transform-object-
rest-spread', and 'transform-async-to-generator' were being used.

3 files changed, 6 insertions, 182 deletions

diff --git a/.babelrc b/.babelrc
index cfa759dd9..a5317cdc5 100644
--- a/.babelrc
+++ b/.babelrc
@@ -12,12 +12,12 @@
         }
       }
     ],
-    "react",
-    "stage-0"
+    "react"
   ],
   "plugins": [
     "transform-runtime",
     "transform-async-to-generator",
-    "transform-class-properties"
+    "transform-class-properties",
+    "transform-object-rest-spread"
   ]
-}
\ No newline at end of file
+}
diff --git a/package-lock.json b/package-lock.json
index 8d45bff12..ad86703b0 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -8213,17 +8213,6 @@
         }
       }
     },
-    "babel-helper-bindify-decorators": {
-      "version": "6.24.1",
-      "resolved": "https://registry.npmjs.org/babel-helper-bindify-decorators/-/babel-helper-bindify-decorators-6.24.1.tgz",
-      "integrity": "sha1-FMGeXxQte0fxmlJDHlKxzLxAozA=",
-      "dev": true,
-      "requires": {
-        "babel-runtime": "^6.22.0",
-        "babel-traverse": "^6.24.1",
-        "babel-types": "^6.24.1"
-      }
-    },
     "babel-helper-builder-binary-assignment-operator-visitor": {
       "version": "6.24.1",
       "resolved": "https://registry.npmjs.org/babel-helper-builder-binary-assignment-operator-visitor/-/babel-helper-builder-binary-assignment-operator-visitor-6.24.1.tgz",
@@ -8283,18 +8272,6 @@
         "babel-types": "^6.24.1"
       }
     },
-    "babel-helper-explode-class": {
-      "version": "6.24.1",
-      "resolved": "https://registry.npmjs.org/babel-helper-explode-class/-/babel-helper-explode-class-6.24.1.tgz",
-      "integrity": "sha1-fcKjkQ3uAHBW4eMdZAztPVTqqes=",
-      "dev": true,
-      "requires": {
-        "babel-helper-bindify-decorators": "^6.24.1",
-        "babel-runtime": "^6.22.0",
-        "babel-traverse": "^6.24.1",
-        "babel-types": "^6.24.1"
-      }
-    },
     "babel-helper-flip-expressions": {
       "version": "0.4.3",
       "resolved": "https://registry.npmjs.org/babel-helper-flip-expressions/-/babel-helper-flip-expressions-0.4.3.tgz",
@@ -8710,65 +8687,23 @@
       "resolved": "https://registry.npmjs.org/babel-plugin-syntax-async-functions/-/babel-plugin-syntax-async-functions-6.13.0.tgz",
       "integrity": "sha1-ytnK0RkbWtY0vzCuCHI5HgZHvpU="
     },
-    "babel-plugin-syntax-async-generators": {
-      "version": "6.13.0",
-      "resolved": "https://registry.npmjs.org/babel-plugin-syntax-async-generators/-/babel-plugin-syntax-async-generators-6.13.0.tgz",
-      "integrity": "sha1-a8lj67FuzLrmuStZbrfzXDQqi5o=",
-      "dev": true
-    },
-    "babel-plugin-syntax-class-constructor-call": {
-      "version": "6.18.0",
-      "resolved": "https://registry.npmjs.org/babel-plugin-syntax-class-constructor-call/-/babel-plugin-syntax-class-constructor-call-6.18.0.tgz",
-      "integrity": "sha1-nLnTn+Q8hgC+yBRkVt3L1OGnZBY=",
-      "dev": true
-    },
     "babel-plugin-syntax-class-properties": {
       "version": "6.13.0",
       "resolved": "https://registry.npmjs.org/babel-plugin-syntax-class-properties/-/babel-plugin-syntax-class-properties-6.13.0.tgz",
       "integrity": "sha1-1+sjt5oxf4VDlixQW4J8fWysJ94=",
       "dev": true
     },
-    "babel-plugin-syntax-decorators": {
-      "version": "6.13.0",
-      "resolved": "https://registry.npmjs.org/babel-plugin-syntax-decorators/-/babel-plugin-syntax-decorators-6.13.0.tgz",
-      "integrity": "sha1-MSVjtNvePMgGzuPkFszurd0RrAs=",
-      "dev": true
-    },
-    "babel-plugin-syntax-do-expressions": {
-      "version": "6.13.0",
-      "resolved": "https://registry.npmjs.org/babel-plugin-syntax-do-expressions/-/babel-plugin-syntax-do-expressions-6.13.0.tgz",
-      "integrity": "sha1-V0d1YTmqJtOQ0JQQsDdEugfkeW0=",
-      "dev": true
-    },
-    "babel-plugin-syntax-dynamic-import": {
-      "version": "6.18.0",
-      "resolved": "https://registry.npmjs.org/babel-plugin-syntax-dynamic-import/-/babel-plugin-syntax-dynamic-import-6.18.0.tgz",
-      "integrity": "sha1-jWomIpyDdFqZgqRBBRVyyqF5sdo=",
-      "dev": true
-    },
     "babel-plugin-syntax-exponentiation-operator": {
       "version": "6.13.0",
       "resolved": "https://registry.npmjs.org/babel-plugin-syntax-exponentiation-operator/-/babel-plugin-syntax-exponentiation-operator-6.13.0.tgz",
       "integrity": "sha1-nufoM3KQ2pUoggGmpX9BcDF4MN4="
     },
-    "babel-plugin-syntax-export-extensions": {
-      "version": "6.13.0",
-      "resolved": "https://registry.npmjs.org/babel-plugin-syntax-export-extensions/-/babel-plugin-syntax-export-extensions-6.13.0.tgz",
-      "integrity": "sha1-cKFITw+QiaToStRLrDU8lbmxJyE=",
-      "dev": true
-    },
     "babel-plugin-syntax-flow": {
       "version": "6.18.0",
       "resolved": "https://registry.npmjs.org/babel-plugin-syntax-flow/-/babel-plugin-syntax-flow-6.18.0.tgz",
       "integrity": "sha1-TDqyCiryaqIM0lmVw5jE63AxDI0=",
       "dev": true
     },
-    "babel-plugin-syntax-function-bind": {
-      "version": "6.13.0",
-      "resolved": "https://registry.npmjs.org/babel-plugin-syntax-function-bind/-/babel-plugin-syntax-function-bind-6.13.0.tgz",
-      "integrity": "sha1-SMSV8Xe98xqYHnMvVa3AvdJgH0Y=",
-      "dev": true
-    },
     "babel-plugin-syntax-jsx": {
       "version": "6.18.0",
       "resolved": "https://registry.npmjs.org/babel-plugin-syntax-jsx/-/babel-plugin-syntax-jsx-6.18.0.tgz",
@@ -8786,17 +8721,6 @@
       "resolved": "https://registry.npmjs.org/babel-plugin-syntax-trailing-function-commas/-/babel-plugin-syntax-trailing-function-commas-6.22.0.tgz",
       "integrity": "sha1-ugNgk3+NBuQBgKQ/4NVhb/9TLPM="
     },
-    "babel-plugin-transform-async-generator-functions": {
-      "version": "6.24.1",
-      "resolved": "https://registry.npmjs.org/babel-plugin-transform-async-generator-functions/-/babel-plugin-transform-async-generator-functions-6.24.1.tgz",
-      "integrity": "sha1-8FiQAUX9PpkHpt3yjaWfIVJYpds=",
-      "dev": true,
-      "requires": {
-        "babel-helper-remap-async-to-generator": "^6.24.1",
-        "babel-plugin-syntax-async-generators": "^6.5.0",
-        "babel-runtime": "^6.22.0"
-      }
-    },
     "babel-plugin-transform-async-to-generator": {
       "version": "6.24.1",
       "resolved": "https://registry.npmjs.org/babel-plugin-transform-async-to-generator/-/babel-plugin-transform-async-to-generator-6.24.1.tgz",
@@ -8807,17 +8731,6 @@
         "babel-runtime": "^6.22.0"
       }
     },
-    "babel-plugin-transform-class-constructor-call": {
-      "version": "6.24.1",
-      "resolved": "https://registry.npmjs.org/babel-plugin-transform-class-constructor-call/-/babel-plugin-transform-class-constructor-call-6.24.1.tgz",
-      "integrity": "sha1-gNwoVQWsBn3LjWxl4vbxGrd2Xvk=",
-      "dev": true,
-      "requires": {
-        "babel-plugin-syntax-class-constructor-call": "^6.18.0",
-        "babel-runtime": "^6.22.0",
-        "babel-template": "^6.24.1"
-      }
-    },
     "babel-plugin-transform-class-properties": {
       "version": "6.24.1",
       "resolved": "https://registry.npmjs.org/babel-plugin-transform-class-properties/-/babel-plugin-transform-class-properties-6.24.1.tgz",
@@ -8830,29 +8743,6 @@
         "babel-template": "^6.24.1"
       }
     },
-    "babel-plugin-transform-decorators": {
-      "version": "6.24.1",
-      "resolved": "https://registry.npmjs.org/babel-plugin-transform-decorators/-/babel-plugin-transform-decorators-6.24.1.tgz",
-      "integrity": "sha1-eIAT2PjGtSIr33s0Q5Df13Vp4k0=",
-      "dev": true,
-      "requires": {
-        "babel-helper-explode-class": "^6.24.1",
-        "babel-plugin-syntax-decorators": "^6.13.0",
-        "babel-runtime": "^6.22.0",
-        "babel-template": "^6.24.1",
-        "babel-types": "^6.24.1"
-      }
-    },
-    "babel-plugin-transform-do-expressions": {
-      "version": "6.22.0",
-      "resolved": "https://registry.npmjs.org/babel-plugin-transform-do-expressions/-/babel-plugin-transform-do-expressions-6.22.0.tgz",
-      "integrity": "sha1-KMyvkoEtlJws0SgfaQyP3EaK6bs=",
-      "dev": true,
-      "requires": {
-        "babel-plugin-syntax-do-expressions": "^6.8.0",
-        "babel-runtime": "^6.22.0"
-      }
-    },
     "babel-plugin-transform-es2015-arrow-functions": {
       "version": "6.22.0",
       "resolved": "https://registry.npmjs.org/babel-plugin-transform-es2015-arrow-functions/-/babel-plugin-transform-es2015-arrow-functions-6.22.0.tgz",
@@ -9075,16 +8965,6 @@
         "babel-runtime": "^6.22.0"
       }
     },
-    "babel-plugin-transform-export-extensions": {
-      "version": "6.22.0",
-      "resolved": "https://registry.npmjs.org/babel-plugin-transform-export-extensions/-/babel-plugin-transform-export-extensions-6.22.0.tgz",
-      "integrity": "sha1-U3OLR+deghhYnuqUbLvTkQm75lM=",
-      "dev": true,
-      "requires": {
-        "babel-plugin-syntax-export-extensions": "^6.8.0",
-        "babel-runtime": "^6.22.0"
-      }
-    },
     "babel-plugin-transform-flow-strip-types": {
       "version": "6.22.0",
       "resolved": "https://registry.npmjs.org/babel-plugin-transform-flow-strip-types/-/babel-plugin-transform-flow-strip-types-6.22.0.tgz",
@@ -9095,16 +8975,6 @@
         "babel-runtime": "^6.22.0"
       }
     },
-    "babel-plugin-transform-function-bind": {
-      "version": "6.22.0",
-      "resolved": "https://registry.npmjs.org/babel-plugin-transform-function-bind/-/babel-plugin-transform-function-bind-6.22.0.tgz",
-      "integrity": "sha1-xvuOlqwpajELjPjqQBRiQH3fapc=",
-      "dev": true,
-      "requires": {
-        "babel-plugin-syntax-function-bind": "^6.8.0",
-        "babel-runtime": "^6.22.0"
-      }
-    },
     "babel-plugin-transform-inline-consecutive-adds": {
       "version": "0.4.3",
       "resolved": "https://registry.npmjs.org/babel-plugin-transform-inline-consecutive-adds/-/babel-plugin-transform-inline-consecutive-adds-0.4.3.tgz",
@@ -9792,53 +9662,6 @@
         }
       }
     },
-    "babel-preset-stage-0": {
-      "version": "6.24.1",
-      "resolved": "https://registry.npmjs.org/babel-preset-stage-0/-/babel-preset-stage-0-6.24.1.tgz",
-      "integrity": "sha1-VkLRUEL5E4TX5a+LyIsduVsDnmo=",
-      "dev": true,
-      "requires": {
-        "babel-plugin-transform-do-expressions": "^6.22.0",
-        "babel-plugin-transform-function-bind": "^6.22.0",
-        "babel-preset-stage-1": "^6.24.1"
-      }
-    },
-    "babel-preset-stage-1": {
-      "version": "6.24.1",
-      "resolved": "https://registry.npmjs.org/babel-preset-stage-1/-/babel-preset-stage-1-6.24.1.tgz",
-      "integrity": "sha1-dpLNfc1oSZB+auSgqFWJz7niv7A=",
-      "dev": true,
-      "requires": {
-        "babel-plugin-transform-class-constructor-call": "^6.24.1",
-        "babel-plugin-transform-export-extensions": "^6.22.0",
-        "babel-preset-stage-2": "^6.24.1"
-      }
-    },
-    "babel-preset-stage-2": {
-      "version": "6.24.1",
-      "resolved": "https://registry.npmjs.org/babel-preset-stage-2/-/babel-preset-stage-2-6.24.1.tgz",
-      "integrity": "sha1-2eKWD7PXEYfw5k7sYrwHdnIZvcE=",
-      "dev": true,
-      "requires": {
-        "babel-plugin-syntax-dynamic-import": "^6.18.0",
-        "babel-plugin-transform-class-properties": "^6.24.1",
-        "babel-plugin-transform-decorators": "^6.24.1",
-        "babel-preset-stage-3": "^6.24.1"
-      }
-    },
-    "babel-preset-stage-3": {
-      "version": "6.24.1",
-      "resolved": "https://registry.npmjs.org/babel-preset-stage-3/-/babel-preset-stage-3-6.24.1.tgz",
-      "integrity": "sha1-g2raCp56f6N8sTj7kyb4eTSkg5U=",
-      "dev": true,
-      "requires": {
-        "babel-plugin-syntax-trailing-function-commas": "^6.22.0",
-        "babel-plugin-transform-async-generator-functions": "^6.24.1",
-        "babel-plugin-transform-async-to-generator": "^6.24.1",
-        "babel-plugin-transform-exponentiation-operator": "^6.24.1",
-        "babel-plugin-transform-object-rest-spread": "^6.22.0"
-      }
-    },
     "babel-register": {
       "version": "6.26.0",
       "resolved": "https://registry.npmjs.org/babel-register/-/babel-register-6.26.0.tgz",
diff --git a/package.json b/package.json
index d3ccbaa48..aa733ffca 100644
--- a/package.json
+++ b/package.json
@@ -177,11 +177,12 @@
     "babel-core": "^6.26.3",
     "babel-eslint": "^8.0.0",
     "babel-plugin-transform-async-to-generator": "^6.24.1",
+    "babel-plugin-transform-class-properties": "^6.24.1",
+    "babel-plugin-transform-object-rest-spread": "^6.22.0",
     "babel-plugin-transform-runtime": "^6.23.0",
     "babel-polyfill": "^6.23.0",
     "babel-preset-env": "^1.7.0",
     "babel-preset-react": "^6.24.1",
-    "babel-preset-stage-0": "^6.24.1",
     "babel-register": "^6.7.2",
     "babelify": "^8.0.0",
     "brfs": "^1.6.1",