Refactor ShortcutHelper and merge in BookmarkUtils

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

Index: chrome/android/java/src/org/chromium/chrome/browser/webapps/AddToHomescreenDialogHelper.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/webapps/AddToHomescreenDialogHelper.java b/chrome/android/java/src/org/chromium/chrome/browser/webapps/AddToHomescreenDialogHelper.java
new file mode 100644
index 0000000000000000000000000000000000000000..d31737a9f659a011af5a91725ffcb438d7294f87
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/webapps/AddToHomescreenDialogHelper.java
@@ -0,0 +1,104 @@
+// 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.Context;
+import android.graphics.Bitmap;
+
+import org.chromium.base.ApplicationStatus;
+import org.chromium.base.annotations.CalledByNative;
+import org.chromium.chrome.browser.ShortcutHelper;
+import org.chromium.chrome.browser.tab.Tab;
+import org.chromium.content_public.browser.WebContents;
+
+/**
+ * This is a helper class to create shortcuts on the Android home screen.
+ */
+public class AddToHomescreenDialogHelper {
+
+    /** Observes the data fetching pipeline. */
+    public interface Observer {
+        /** Called when the title of the page is available. */
+        void onUserTitleAvailable(String title);
+
+        /** Called when the icon to use in the launcher is available. */
+        void onIconAvailable(Bitmap icon);
+    }
+
+    private final Context mAppContext;
+    private final Tab mTab;
+
+    private Observer mObserver;
+    private boolean mIsInitialized;
+    private long mNativeAddToHomescreenDialogHelper;
+
+    public AddToHomescreenDialogHelper(Context appContext, Tab tab) {
+        mAppContext = appContext;
+        mTab = tab;
+    }
+
+    /**
+     * Gets all the information required to initialize the UI.  The observer will be notified as
+     * information required for the shortcut become available.
+     * @param observer Observer to notify.
+     */
+    public void initialize(Observer observer) {
+        mObserver = observer;
+        mNativeAddToHomescreenDialogHelper = nativeInitialize(mTab.getWebContents());
+    }
+
+    /**
+     * Returns whether the object is initialized.
+     */
+    public boolean isInitialized() {
+        return mIsInitialized;
+    }
+
+    /**
+     * Puts the object in a state where it is safe to be destroyed.
+     */
+    public void destroy() {
+        nativeDestroy(mNativeAddToHomescreenDialogHelper);
+
+        // Make sure the callback isn't run if the tear down happens before
+        // onInitialized() is called.
+        mObserver = null;
+        mNativeAddToHomescreenDialogHelper = 0;
+    }
+
+    @CalledByNative
+    private void onUserTitleAvailable(String title) {
+        mObserver.onUserTitleAvailable(title);
+    }
+
+    @CalledByNative
+    private void onIconAvailable(Bitmap icon) {
+        mObserver.onIconAvailable(icon);
+        mIsInitialized = true;
+    }
+
+    /**
+     * Adds a shortcut for the current Tab.
+     * @param userRequestedTitle Updated title for the shortcut.
+     */
+    public void addShortcut(String userRequestedTitle) {
+        nativeAddShortcut(mNativeAddToHomescreenDialogHelper, userRequestedTitle);
+    }
+
+    /**
+     * Creates an icon that is acceptable to show on the launcher.
+     */
+    @CalledByNative
+    private static Bitmap finalizeLauncherIcon(
+            String url, Bitmap icon, int red, int green, int blue) {
+        return ShortcutHelper.createLauncherIcon(
+                ApplicationStatus.getApplicationContext(), icon, url, red, green, blue);
+    }
+
+    private native long nativeInitialize(WebContents webContents);
+    private native void nativeAddShortcut(long nativeAddToHomescreenDialogHelper,
+            String userRequestedTitle);
+    private native void nativeDestroy(long nativeAddToHomescreenDialogHelper);
+}