Add ability to import v3 JSON wallets

There is now a menu item labeled "JSON File" for importing, and it can digest either:
- v1 MyEtherWallet JSON files
- v3 Account files (used by Geth, Mist, and MyEtherWallet).

Fixes #715

app/scripts/account-import-strategies/index.js

@@ -7,8 +7,7 @@ const accountImporter = {
   importAccount(strategy, args) {
     try {
       const importer = this.strategies[strategy]
-      const wallet = importer.apply(null, args)
-      const privateKeyHex = walletToPrivateKey(wallet)
+      const privateKeyHex = importer.apply(null, args)
       return Promise.resolve(privateKeyHex)
     } catch (e) {
       return Promise.reject(e)
@@ -18,11 +17,20 @@ const accountImporter = {
   strategies: {
     'Private Key': (privateKey) => {
       const stripped = ethUtil.stripHexPrefix(privateKey)
-      const buffer = new Buffer(stripped, 'hex')
-      return Wallet.fromPrivateKey(buffer)
+      return stripped
     },
     'JSON File': (input, password) => {
-      const wallet = importers.fromEtherWallet(input, password)
+      let wallet
+      try {
+        wallet = importers.fromEtherWallet(input, password)
+      } catch (e) {
+        console.log('Attempt to import as EtherWallet format failed, trying V3...')
+      }
+
+      if (!wallet) {
+        wallet = Wallet.fromV3(input, password, true)
+      }
+
       return walletToPrivateKey(wallet)
     },
   },

ui/app/actions.js

@@ -267,7 +267,7 @@ function addNewKeyring (type, opts) {
 
 function importNewAccount (strategy, args) {
   return (dispatch) => {
-    dispatch(actions.showLoadingIndication())
+    dispatch(actions.showLoadingIndication('This may take a while, be patient.'))
     background.importAccountWithStrategy(strategy, args, (err, newState) => {
       dispatch(actions.hideLoadingIndication())
       if (err) return dispatch(actions.displayWarning(err.message))
@@ -630,9 +630,10 @@ function useEtherscanProvider () {
   }
 }
 
-function showLoadingIndication () {
+function showLoadingIndication (message) {
   return {
     type: actions.SHOW_LOADING,
+    value: message,
   }
 }
 

ui/app/app.js

@@ -43,6 +43,7 @@ function mapStateToProps (state) {
   return {
     // state from plugin
     isLoading: state.appState.isLoading,
+    loadingMessage: state.appState.loadingMessage,
     isDisclaimerConfirmed: state.metamask.isDisclaimerConfirmed,
     noActiveNotices: state.metamask.noActiveNotices,
     isInitialized: state.metamask.isInitialized,
@@ -64,7 +65,7 @@ function mapStateToProps (state) {
 
 App.prototype.render = function () {
   var props = this.props
-  const { isLoading, transForward } = props
+  const { isLoading, loadingMessage, transForward } = props
 
   return (
 
@@ -76,7 +77,7 @@ App.prototype.render = function () {
       },
     }, [
 
-      h(LoadingIndicator, { isLoading }),
+      h(LoadingIndicator, { isLoading, loadingMessage }),
 
       // app bar
       this.renderAppBar(),

ui/app/components/loading.js

@@ -12,7 +12,7 @@ function LoadingIndicator () {
 }
 
 LoadingIndicator.prototype.render = function () {
-  var isLoading = this.props.isLoading
+  const { isLoading, loadingMessage } = this.props
 
   return (
     h(ReactCSSTransitionGroup, {
@@ -37,8 +37,14 @@ LoadingIndicator.prototype.render = function () {
         h('img', {
           src: 'images/loading.svg',
         }),
+
+        showMessageIfAny(loadingMessage),
       ]) : null,
     ])
   )
 }
 
+function showMessageIfAny (loadingMessage) {
+  if (!loadingMessage) return null
+  return h('span', loadingMessage)
+}

ui/app/reducers/app.js

@@ -386,6 +386,7 @@ function reduceApp (state, action) {
     case actions.SHOW_LOADING:
       return extend(appState, {
         isLoading: true,
+        loadingMessage: action.value,
       })
 
     case actions.HIDE_LOADING: