Init WebApkUpdateManager with a WebappDataStorage to avoid null object.

chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappActivity.java

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.chrome.browser.webapps;
 
 import android.content.Intent;
 import android.graphics.Bitmap;
 import android.graphics.Color;
 import android.graphics.drawable.Drawable;
@@ skipping 276 matching lines @@
         super.onResume();
     }
 
     @Override
     public void onResumeWithNative() {
         super.onResumeWithNative();
         mWebappUma.commitMetrics();
     }
 
     @Override
+    public void onDeferredStartup() {
+        super.onDeferredStartup();
+
+        WebappDataStorage storage =
+                WebappRegistry.getInstance().getWebappDataStorage(mWebappInfo.id());
+        if (storage != null) {
+            onDeferredStartupWithStorage(storage);
+        } else {
+            onDeferredStartupWithNullStorage();
+        }
+    }
+
+    protected void onDeferredStartupWithStorage(WebappDataStorage storage) {
+        updateStorage(storage);
+    }
+
+    protected void onDeferredStartupWithNullStorage() {
+        return;
+    }
+
+    @Override
     protected int getControlContainerLayoutId() {
         return R.layout.webapp_control_container;
     }
 
     @Override
     public void postInflationStartup() {
         initializeWebappData();
 
         super.postInflationStartup();
         WebappControlContainer controlContainer =
@@ skipping 34 matching lines @@
                 ? WebappUma.SPLASHSCREEN_COLOR_STATUS_CUSTOM
                 : WebappUma.SPLASHSCREEN_COLOR_STATUS_DEFAULT);
 
         initializeSplashScreenWidgets(backgroundColor);
     }
 
     protected void initializeSplashScreenWidgets(final int backgroundColor) {
         WebappDataStorage storage =
                 WebappRegistry.getInstance().getWebappDataStorage(mWebappInfo.id());
         if (storage == null) {
-            onStorageIsNull(backgroundColor);
+            initializeSplashScreenWidgets(backgroundColor, null);
             return;
         }
 
-        updateStorage(storage);
         storage.getSplashScreenImage(new WebappDataStorage.FetchCallback<Bitmap>() {
             @Override
             public void onDataRetrieved(Bitmap splashImage) {
                 initializeSplashScreenWidgets(backgroundColor, splashImage);
             }
         });
     }
 
-    protected void onStorageIsNull(int backgroundColor) {}
-
     protected void updateStorage(WebappDataStorage storage) {
         // The information in the WebappDataStorage may have been purged by the
         // user clearing their history or not launching the web app recently.
         // Restore the data if necessary from the intent.
         storage.updateFromShortcutIntent(getIntent());
 
         // A recent last used time is the indicator that the web app is still
         // present on the home screen, and enables sources such as notifications to
         // launch web apps. Thus, we do not update the last used time when the web
         // app is not directly launched from the home screen, as this interferes
@@ skipping 299 matching lines @@
         return new WebappDelegateFactory(this);
     }
 
     // We're temporarily disable CS on webapp since there are some issues. (http://crbug.com/471950)
     // TODO(changwan): re-enable it once the issues are resolved.
     @Override
     protected boolean isContextualSearchAllowed() {
         return false;
     }
 }