diff --git a/gfx/tests/gtest/TestAsyncPanZoomController.cpp b/gfx/tests/gtest/TestAsyncPanZoomController.cpp
index 0f910e86f8c..deca73fae64 100644
--- a/gfx/tests/gtest/TestAsyncPanZoomController.cpp
+++ b/gfx/tests/gtest/TestAsyncPanZoomController.cpp
@@ -66,6 +66,7 @@ public:
   MOCK_METHOD3(HandleLongTapUp, void(const CSSPoint&, int32_t, const ScrollableLayerGuid&));
   MOCK_METHOD3(SendAsyncScrollDOMEvent, void(bool aIsRoot, const CSSRect &aContentRect, const CSSSize &aScrollableSize));
   MOCK_METHOD2(PostDelayedTask, void(Task* aTask, int aDelayMs));
+  MOCK_METHOD3(NotifyAPZStateChange, void(const ScrollableLayerGuid& aGuid, APZStateChange aChange, int aArg));
 };
 
 class MockContentControllerDelayed : public MockContentController {
@@ -934,6 +935,45 @@ TEST_F(APZCBasicTester, FlingIntoOverscroll) {
   EXPECT_TRUE(recoveredFromOverscroll);
 }
 
+TEST_F(APZCBasicTester, PanningTransformNotifications) {
+  SCOPED_GFX_PREF(APZOverscrollEnabled, bool, true);
+
+  // Scroll down by 25 px. Ensure we only get one set of
+  // state change notifications.
+  //
+  // Then, scroll back up by 20px, this time flinging after.
+  // The fling should cover the remaining 5 px of room to scroll, then
+  // go into overscroll, and finally snap-back to recover from overscroll.
+  // Again, ensure we only get one set of state change notifications for
+  // this entire procedure.
+
+  MockFunction<void(std::string checkPointName)> check;
+  {
+    InSequence s;
+    EXPECT_CALL(check, Call("Simple pan"));
+    EXPECT_CALL(*mcc, NotifyAPZStateChange(_,GeckoContentController::APZStateChange::StartTouch,_)).Times(1);
+    EXPECT_CALL(*mcc, NotifyAPZStateChange(_,GeckoContentController::APZStateChange::TransformBegin,_)).Times(1);
+    EXPECT_CALL(*mcc, NotifyAPZStateChange(_,GeckoContentController::APZStateChange::StartPanning,_)).Times(1);
+    EXPECT_CALL(*mcc, NotifyAPZStateChange(_,GeckoContentController::APZStateChange::EndTouch,_)).Times(1);
+    EXPECT_CALL(*mcc, NotifyAPZStateChange(_,GeckoContentController::APZStateChange::TransformEnd,_)).Times(1);
+    EXPECT_CALL(check, Call("Complex pan"));
+    EXPECT_CALL(*mcc, NotifyAPZStateChange(_,GeckoContentController::APZStateChange::StartTouch,_)).Times(1);
+    EXPECT_CALL(*mcc, NotifyAPZStateChange(_,GeckoContentController::APZStateChange::TransformBegin,_)).Times(1);
+    EXPECT_CALL(*mcc, NotifyAPZStateChange(_,GeckoContentController::APZStateChange::StartPanning,_)).Times(1);
+    EXPECT_CALL(*mcc, NotifyAPZStateChange(_,GeckoContentController::APZStateChange::EndTouch,_)).Times(1);
+    EXPECT_CALL(*mcc, NotifyAPZStateChange(_,GeckoContentController::APZStateChange::TransformEnd,_)).Times(1);
+    EXPECT_CALL(check, Call("Done"));
+  }
+
+  int time = 0;
+  check.Call("Simple pan");
+  ApzcPanNoFling(apzc, time, 50, 25);
+  check.Call("Complex pan");
+  ApzcPan(apzc, time, 25, 45);
+  apzc->AdvanceAnimationsUntilEnd(testStartTime);
+  check.Call("Done");
+}
+
 TEST_F(APZCBasicTester, OverScrollPanning) {
   SCOPED_GFX_PREF(APZOverscrollEnabled, bool, true);