Remove `seedWords` completely from metamask state (#6920)

`seedWords` used to be stored on the metamask state temporarily at
certain points. This hasn't been the case since #5994, but references
to this state remained. All of the logic remained for correctly updating
these `seedWords`, handling them during navigation, and scrubbing them
from the state.

However the state was never updated in practice. The `seedWords` are
still returned by `verifySeedPhrase`, and they're still stored in
component state in a few places. But they aren't ever set in the Redux
metadata state or the Preferences controller.

All references to this state have been removed, along with any logic
for interacting with this state. A few unused actions were removed as
well.

3 files changed, 3 insertions, 45 deletions

diff --git a/ui/app/ducks/app/app.js b/ui/app/ducks/app/app.js
index 04c8c7422..77d9116e5 100644
--- a/ui/app/ducks/app/app.js
+++ b/ui/app/ducks/app/app.js
@@ -27,13 +27,6 @@ function reduceApp (state, action) {
     context: selectedAddress,
   }
 
-  // confirm seed words
-  var seedWords = state.metamask.seedWords
-  var seedConfView = {
-    name: 'createVaultComplete',
-    seedWords,
-  }
-
   // default state
   var appState = extend({
     shouldClose: false,
@@ -58,7 +51,7 @@ function reduceApp (state, action) {
     alertMessage: null,
     qrCodeData: null,
     networkDropdownOpen: false,
-    currentView: seedWords ? seedConfView : defaultView,
+    currentView: defaultView,
     accountDetail: {
       subview: 'transactions',
     },
@@ -279,16 +272,6 @@ function reduceApp (state, action) {
         isLoading: true,
       })
 
-    case actions.SHOW_NEW_VAULT_SEED:
-      return extend(appState, {
-        currentView: {
-          name: 'createVaultComplete',
-          seedWords: action.value,
-        },
-        transForward: true,
-        isLoading: false,
-      })
-
     case actions.NEW_ACCOUNT_SCREEN:
       return extend(appState, {
         currentView: {
@@ -428,8 +411,7 @@ function reduceApp (state, action) {
     case actions.SHOW_ACCOUNTS_PAGE:
       return extend(appState, {
         currentView: {
-          name: seedWords ? 'createVaultComplete' : 'accounts',
-          seedWords,
+          name: 'accounts',
         },
         transForward: true,
         isLoading: false,
diff --git a/ui/app/ducks/index.js b/ui/app/ducks/index.js
index 2d33edcfa..18470c441 100644
--- a/ui/app/ducks/index.js
+++ b/ui/app/ducks/index.js
@@ -61,9 +61,6 @@ window.getCleanAppState = function () {
   // append additional information
   state.version = global.platform.getVersion()
   state.browser = window.navigator.userAgent
-  // ensure seedWords are not included
-  if (state.metamask) delete state.metamask.seedWords
-  if (state.appState.currentView) delete state.appState.currentView.seedWords
   return state
 }
 
@@ -72,7 +69,7 @@ window.logStateString = function (cb) {
   global.platform.getPlatformInfo((err, platform) => {
     if (err) return cb(err)
     state.platform = platform
-    const stateString = JSON.stringify(state, removeSeedWords, 2)
+    const stateString = JSON.stringify(state, null, 2)
     cb(null, stateString)
   })
 }
@@ -89,7 +86,3 @@ window.logState = function (toClipboard) {
     }
   })
 }
-
-function removeSeedWords (key, value) {
-  return key === 'seedWords' ? undefined : value
-}
diff --git a/ui/app/ducks/metamask/metamask.js b/ui/app/ducks/metamask/metamask.js
index 64ce064b9..92f190cf1 100644
--- a/ui/app/ducks/metamask/metamask.js
+++ b/ui/app/ducks/metamask/metamask.js
@@ -44,7 +44,6 @@ function reduceMetamask (state, action) {
     useBlockie: false,
     featureFlags: {},
     networkEndpointType: OLD_UI_NETWORK_TYPE,
-    isRevealingSeedWords: false,
     welcomeScreenSeen: false,
     currentLocale: '',
     preferences: {
@@ -60,13 +59,6 @@ function reduceMetamask (state, action) {
 
   switch (action.type) {
 
-    case actions.SHOW_ACCOUNTS_PAGE:
-      newState = extend(metamaskState, {
-        isRevealingSeedWords: false,
-      })
-      delete newState.seedWords
-      return newState
-
     case actions.UPDATE_METAMASK_STATE:
       return extend(metamaskState, action.value)
 
@@ -128,20 +120,12 @@ function reduceMetamask (state, action) {
         },
       })
 
-
-    case actions.SHOW_NEW_VAULT_SEED:
-      return extend(metamaskState, {
-        isRevealingSeedWords: true,
-        seedWords: action.value,
-      })
-
     case actions.CLEAR_SEED_WORD_CACHE:
       newState = extend(metamaskState, {
         isUnlocked: true,
         isInitialized: true,
         selectedAddress: action.value,
       })
-      delete newState.seedWords
       return newState
 
     case actions.SHOW_ACCOUNT_DETAIL:
@@ -150,7 +134,6 @@ function reduceMetamask (state, action) {
         isInitialized: true,
         selectedAddress: action.value,
       })
-      delete newState.seedWords
       return newState
 
     case actions.SET_SELECTED_TOKEN: