Only signal collection swap on true swap

bug:7484054

Change-Id: I7cb648f64f45711013996be7e2cd0dabdbd614ae
diff --git a/Source/WebCore/platform/graphics/android/rendering/SurfaceCollectionManager.cpp b/Source/WebCore/platform/graphics/android/rendering/SurfaceCollectionManager.cpp
index 9914176..f3ff0cf 100644
--- a/Source/WebCore/platform/graphics/android/rendering/SurfaceCollectionManager.cpp
+++ b/Source/WebCore/platform/graphics/android/rendering/SurfaceCollectionManager.cpp
@@ -304,10 +304,6 @@
     if (m_drawingCollection) {
         bool drawingReady = didCollectionSwap || m_drawingCollection->isReady();
 
-        // call the page swap callback if registration happened without more collections enqueued
-        if (collectionsSwappedPtr && drawingReady && !m_paintingCollection)
-            *collectionsSwappedPtr = true;
-
         if (didCollectionSwap || m_fastSwapMode || (drawingReady && !m_paintingCollection))
             m_drawingCollection->swapTiles();