webapps: initial addition of splash screen icon downloading

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

Index: chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappDataStorage.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappDataStorage.java b/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappDataStorage.java
index 748883e2c19ac3d657c0620881881775dc755490..6b38852d947b4b0413afa10d2762e90a5b51de20 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappDataStorage.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappDataStorage.java
@@ -10,6 +10,7 @@ import android.graphics.Bitmap;
 import android.os.AsyncTask;
 
 import org.chromium.base.ThreadUtils;
+import org.chromium.base.VisibleForTesting;
 import org.chromium.chrome.browser.ShortcutHelper;
 
 /**
@@ -30,6 +31,8 @@ public class WebappDataStorage {
     static final String KEY_LAST_USED = "last_used";
     static final long INVALID_LAST_USED = -1;
 
+    private static Observer sObserver = null;
+
     private final SharedPreferences mPreferences;
 
     /**
@@ -76,6 +79,14 @@ public class WebappDataStorage {
         }.execute();
     }
 
+    /**
+     * Sets the observer to use.
+     */
+    @VisibleForTesting
+    public static void setObserverForTests(Observer observer) {

[mlamouri (slow - plz ping), 2015/09/03 22:58:40]

So, after talking with you and Dan, I think we should have a
WebappDataStorageWrapper in the tests that will overload
updateSplashScreenImage().

[Lalit Maganti, 2015/09/04 11:13:24]

Changed as discussed.

+        sObserver = observer;
+    }
+
     /** Package private for use by WebappRegistry */
     WebappDataStorage(Context context, String webappId) {
         mPreferences = context.getSharedPreferences(
@@ -97,6 +108,7 @@ public class WebappDataStorage {
      * @param splashScreenImage The image which should be shown on the splash screen of the web app.
      */
     public void updateSplashScreenImage(Bitmap splashScreenImage) {
+        if (sObserver != null) sObserver.onUpdateSplashScreenImage(splashScreenImage);
         new UpdateTask(splashScreenImage).execute();
     }
 
@@ -118,6 +130,18 @@ public class WebappDataStorage {
         public void onDataRetrieved(T readObject);
     }
 
+    /**
+     * Observer used to monitor splash screen downloads.
+     */
+    public static interface Observer {
+
+        /**
+         * Called when a splash screen update is queued.
+         */
+        @VisibleForTesting
+        public void onUpdateSplashScreenImage(Bitmap image);
+    }
+
     private final class BitmapFetchTask extends AsyncTask<Void, Void, Bitmap> {
 
         private final String mKey;