fix(onboarding): fix error handling for invalid account data from server

Summary:
Change `addAccountFromJSON` in `AccountStore` to throw an exception when it encounters
invalid data, instead of calling `atom.emitError()`. Just calling `emitError` doesn't
throw an exception, so the code proceeds as if an account has been added. Instead, call
`emitError` from AccountSettingsPage, and display an error message to the user.

Test Plan: manual

Reviewers: bengotow

Reviewed By: bengotow

Subscribers: evan

Differential Revision: https://phab.nylas.com/D2116

internal_packages/onboarding/lib/account-settings-page.cjsx

@@ -45,7 +45,7 @@ class AccountSettingsPage extends React.Component
               {data} = account_data
               # accountJson = @_decrypt(data, @state.provider.encryptionKey, @state.provider.encryptionIv)
               account = JSON.parse(data)
-              OnboardingActions.accountJSONReceived(account)
+              @_onAccountReceived(account)
             else if tries < 20 and id is pollAttemptId
               setTimeout(_retry, delay)
               delay *= 1.2 # exponential backoff
@@ -251,11 +251,21 @@ class AccountSettingsPage extends React.Component
         method: "POST"
         timeout: 30000
         body: json
-        success: (json) =>
-          OnboardingActions.accountJSONReceived(json)
+        success: @_onAccountReceived
         error: @_onNetworkError
     .catch(@_onNetworkError)
 
+  _onAccountReceived: (json) =>
+    try
+      OnboardingActions.accountJSONReceived(json)
+    catch e
+      atom.emitError(e)
+      @setState
+        tryingToAuthenticate: false
+        errorMessage: "Sorry, something went wrong on the Nylas server. Please try again. If you're still having issues, contact us at support@nylas.com."
+      @_resize()
+
+
   _onNetworkError: (err) =>
     errorMessage = err.message
     if errorMessage == "Invite code required"

src/flux/stores/account-store.coffee

@@ -79,8 +79,7 @@ class AccountStore
     if not json.email_address or not json.provider
       console.error("Returned account data is invalid", json)
       console.log JSON.stringify(json)
-      atom.emitError(new Error("Returned account data is invalid"))
-      return
+      throw new Error("Returned account data is invalid")
     return if @_tokens[json.id]
     @_tokens[json.id] = json.auth_token
     @_accounts.push((new Account).fromJSON(json))