From bb00f53b949c7e25a03d3755d2554d1068120c36 Mon Sep 17 00:00:00 2001
From: Kartikaya Gupta <kgupta@mozilla.com>
Date: Wed, 11 Jan 2012 17:08:14 -0500
Subject: [PATCH] Bug 713011 - Add a check to ensure we are running on the
 correct thread. r=blassey

---
 mobile/android/base/ui/PanZoomController.java | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/mobile/android/base/ui/PanZoomController.java b/mobile/android/base/ui/PanZoomController.java
index 3b0d8c27043..7a85f83ba68 100644
--- a/mobile/android/base/ui/PanZoomController.java
+++ b/mobile/android/base/ui/PanZoomController.java
@@ -124,6 +124,8 @@ public class PanZoomController
     private final Axis mX;
     private final Axis mY;
 
+    private Thread mMainThread;
+
     /* The timer that handles flings or bounces. */
     private Timer mAnimationTimer;
     /* The runnable being scheduled by the animation timer. */
@@ -141,12 +143,23 @@ public class PanZoomController
         mX = new AxisX(mSubscroller);
         mY = new AxisY(mSubscroller);
 
+        mMainThread = GeckoApp.mAppContext.getMainLooper().getThread();
+        checkMainThread();
+
         mState = PanZoomState.NOTHING;
 
         GeckoAppShell.registerGeckoEventListener(MESSAGE_ZOOM_RECT, this);
         GeckoAppShell.registerGeckoEventListener(MESSAGE_ZOOM_PAGE, this);
     }
 
+    // for debugging bug 713011; it can be taken out once that is resolved.
+    private void checkMainThread() {
+        if (mMainThread != Thread.currentThread()) {
+            // log with full stack trace
+            Log.e(LOGTAG, "Uh-oh, we're running on the wrong thread!", new Exception());
+        }
+    }
+
     public void handleMessage(String event, JSONObject message) {
         Log.i(LOGTAG, "Got message: " + event);
         try {
@@ -198,6 +211,7 @@ public class PanZoomController
     /** This function must be called from the UI thread. */
     @SuppressWarnings("fallthrough")
     public void abortAnimation() {
+        checkMainThread();
         // this happens when gecko changes the viewport on us or if the device is rotated.
         // if that's the case, abort any animation in progress and re-zoom so that the page
         // snaps to edges. for other cases (where the user's finger(s) are down) don't do
@@ -631,6 +645,8 @@ public class PanZoomController
     }
 
     private void finishAnimation() {
+        checkMainThread();
+
         Log.d(LOGTAG, "Finishing animation at " + mController.getViewportMetrics());
         stopAnimationTimer();