Split ShortcutHelper#addShortcut() into separate functions for each type of shortcut

chrome/browser/android/shortcut_helper.h

Index: chrome/browser/android/shortcut_helper.h
diff --git a/chrome/browser/android/shortcut_helper.h b/chrome/browser/android/shortcut_helper.h
index 40a4beea782e63685e8a307c9b0d620a46ee0c43..e552adec6da226fcefda43356de1a554748f8c84 100644
--- a/chrome/browser/android/shortcut_helper.h
+++ b/chrome/browser/android/shortcut_helper.h
@@ -23,12 +23,7 @@ class ShortcutHelper {
   // Registers JNI hooks.
   static bool RegisterShortcutHelper(JNIEnv* env);
 
-  // Adds a shortcut to the launcher using a SkBitmap. If the shortcut is for
-  // a standalone-capable site, |splash_image_callback| will be invoked once the
-  // Java-side operation has completed. This is necessary as Java will
-  // asynchronously create and populate a WebappDataStorage object for
-  // standalone-capable sites. This must exist before the splash image can be
-  // stored.
+  // Adds a shortcut to the launcher using a SkBitmap.

[dominickn, 2016/07/15 00:19:00]

Nit: "The type of shortcut added depends on the properties in |info|. Calls one
of AddWebApkInBackgroundWithSkBitmap, AddWebappInBackgroundWithSkBitmap, or
AddBookmarkShortcutInBackgroundWithSkBitmap."

Also, rename this method as per the below comment.

   // Must not be called on the UI thread.
   static void AddShortcutInBackgroundWithSkBitmap(
       const ShortcutInfo& info,
@@ -36,6 +31,31 @@ class ShortcutHelper {
       const SkBitmap& icon_bitmap,
       const base::Closure& splash_image_callback);
 
+  // Installs WebAPK and adds shortcut to the launcher.
+  // Must not be called on the UI thread.
+  static void AddWebApkInBackgroundWithSkBitmap(

[dominickn, 2016/07/15 00:19:00]

Perhaps InstallWebApkInBackgroundWithSkBitmap for consistency with the Java
side?

+      const ShortcutInfo& info,
+      const std::string& webapp_id,
+      const SkBitmap& icon_bitmap);
+
+  // Adds a shortcut which opens in a fullscreen window to the launcher.
+  // |splash_image_callback| will be invoked once the Java-side operation has
+  // completed. This is necessary as Java will asynchronously create and
+  // populate a WebappDataStorage object for standalone-capable sites. This must
+  // exist before the splash image can be stored.
+  // Must not be called on the UI thread.
+  static void AddWebappInBackgroundWithSkBitmap(
+      const ShortcutInfo& info,
+      const std::string& webapp_id,
+      const SkBitmap& icon_bitmap,
+      const base::Closure& splash_image_callback);
+
+  // Adds a shortcut which opens in a browser tab to the launcher.
+  // Must not be called on the UI thread.
+  static void AddBookmarkShortcutInBackgroundWithSkBitmap(

[dominickn, 2016/07/15 00:19:00]

"Bookmark shortcut" is a bit misleading here because these are not equivalent to
bookmarks and don't add a Chrome bookmark. How about
"AddShortcutInBackgroundWithSkBitmap" instead, and the method above with that
name can be "AddToLauncherInBackgroundWithSkBitmap?

+      const ShortcutInfo& info,
+      const SkBitmap& icon_bitmap);
+
   // Returns the ideal size for an icon representing a web app.
   static int GetIdealHomescreenIconSizeInDp();