Clear webapp storage when site data is cleared

chrome/android/java/src/org/chromium/chrome/browser/preferences/privacy/ClearBrowsingDataDialogFragment.java

Index: chrome/android/java/src/org/chromium/chrome/browser/preferences/privacy/ClearBrowsingDataDialogFragment.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/preferences/privacy/ClearBrowsingDataDialogFragment.java b/chrome/android/java/src/org/chromium/chrome/browser/preferences/privacy/ClearBrowsingDataDialogFragment.java
index 6a0b885c1d43b8f6098409ef38b1fde9ff39457f..81add764e8eb89283f2202580b552bbb64d0df42 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/preferences/privacy/ClearBrowsingDataDialogFragment.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/preferences/privacy/ClearBrowsingDataDialogFragment.java
@@ -24,6 +24,7 @@ import android.widget.Button;
 import android.widget.CheckedTextView;
 import android.widget.TextView;
 
+import org.chromium.base.VisibleForTesting;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.preferences.PrefServiceBridge;
 import org.chromium.chrome.browser.preferences.Preferences;
@@ -280,4 +281,9 @@ public class ClearBrowsingDataDialogFragment extends DialogFragment
                 getActivity().getString(R.string.clear_browsing_data_progress_message), true,
                 false);
     }
+
+    @VisibleForTesting
+    ProgressDialog getProgressDialog() {
+        return mProgressDialog;
+    }
 }