Clear webapp storage when site data is cleared

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

Index: chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappRegistry.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappRegistry.java b/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappRegistry.java
index fe19baaa4b8a989dac549b7ba1c400cbc802d928..291159f80cba76887422c0a9eea33690fc736aeb 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappRegistry.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappRegistry.java
@@ -8,6 +8,9 @@ import android.content.Context;
 import android.content.SharedPreferences;
 import android.os.AsyncTask;
 
+import org.chromium.base.VisibleForTesting;
+import org.chromium.base.annotations.CalledByNative;
+
 import java.util.Collections;
 import java.util.HashSet;
 import java.util.Set;
@@ -27,6 +30,13 @@ public class WebappRegistry {
     static final String KEY_WEBAPP_SET = "webapp_set";
 
     /**
+     * Called when a retrieval of the stored web apps occurs.

[gone, 2015/09/09 23:30:39]

nit: You used "webapp" in the added comment for WebappDataStorage, but you used
"web apps" on the comment here -- you should pick one.  Doesn't help that your
class JavaDoc says "webapps" but the JavaDoc for registerWebapp says "web app".

[Lalit Maganti, 2015/09/10 09:41:57]

OK I choose "web app" for all text for consistency and correctness reasons. I'll
change any other instances of this I find.

+     */
+    public interface FetchCallback {
+        public void onWebappIdsRetrieved(Set<String> readObject);
+    }
+
+    /**
      * Registers the existence of a web app and creates the SharedPreference for it.
      * @param context  Context to open the registry with.
      * @param webappId The id of the web app to register.
@@ -35,10 +45,8 @@ public class WebappRegistry {
         new AsyncTask<Void, Void, Void>() {
             @Override
             protected final Void doInBackground(Void... nothing) {
-                SharedPreferences preferences = context.getSharedPreferences(
-                        REGISTRY_FILE_NAME, Context.MODE_PRIVATE);
-                Set<String> webapps = new HashSet<String>(
-                        preferences.getStringSet(KEY_WEBAPP_SET, Collections.<String>emptySet()));
+                SharedPreferences preferences = openSharedPreferences(context);
+                Set<String> webapps = new HashSet<String>(getRegisteredWebappIds(preferences));
                 boolean added = webapps.add(webappId);
                 assert added;
 
@@ -61,9 +69,7 @@ public class WebappRegistry {
         new AsyncTask<Void, Void, Set<String>>() {
             @Override
             protected final Set<String> doInBackground(Void... nothing) {
-                SharedPreferences preferences = context.getSharedPreferences(
-                        REGISTRY_FILE_NAME, Context.MODE_PRIVATE);
-                return preferences.getStringSet(KEY_WEBAPP_SET, Collections.<String>emptySet());
+                return getRegisteredWebappIds(openSharedPreferences(context));
             }
 
             @Override
@@ -73,13 +79,47 @@ public class WebappRegistry {
         }.execute();
     }
 
-    private WebappRegistry() {
+    /** Deletes the data of all webapps as well as the registry tracking the webapps. */

[gone, 2015/09/09 23:30:39]

nit:
replace "as well as" with 
", as well as" or "and"

Also, same comment about settling on either webapps or web apps for new edits.

[Lalit Maganti, 2015/09/10 09:41:57]

Done.

+    @VisibleForTesting
+    static void unregisterAllWebapps(final Context context, final Runnable callback) {
+        new AsyncTask<Void, Void, Void>() {
+            @Override
+            protected final Void doInBackground(Void... nothing) {
+                SharedPreferences preferences = openSharedPreferences(context);
+                for (String id : getRegisteredWebappIds(preferences)) {
+                    WebappDataStorage.deleteDataForWebapp(context, id);
+                }
+                preferences.edit().clear().commit();
+                return null;
+            }
+
+            @Override
+            protected final void onPostExecute(Void nothing) {
+                callback.run();
+            }
+        }.execute();
     }
 
-    /**
-     * Called when a retrieval of the stored web apps occurs.
-     */
-    public interface FetchCallback {
-        public void onWebappIdsRetrieved(Set<String> readObject);
+    @CalledByNative
+    private static void unregisterAllWebapps(Context context, final long callbackPointer) {
+        unregisterAllWebapps(context, new Runnable() {
+            @Override
+            public void run() {
+                nativeOnWebappsUnregistered(callbackPointer);
+            }
+        });
+    }
+
+    private static SharedPreferences openSharedPreferences(Context context) {
+        return context.getSharedPreferences(REGISTRY_FILE_NAME, Context.MODE_PRIVATE);
+    }
+
+    private static Set<String> getRegisteredWebappIds(SharedPreferences preferences) {
+        return preferences.getStringSet(KEY_WEBAPP_SET, Collections.<String>emptySet());
+    }
+
+    private static native void nativeOnWebappsUnregistered(long callbackPointer);

[gone, 2015/09/09 23:30:39]

native call definitions always go at the bottom.

[Lalit Maganti, 2015/09/10 09:41:57]

Done.

+
+    private WebappRegistry() {
     }
 }