Merge "Fix setPositionListener race condition" into qt-dev

libs/hwui/RenderNode.cpp

@@ -264,6 +264,12 @@ void RenderNode::syncProperties() {
 }
 
 void RenderNode::pushStagingPropertiesChanges(TreeInfo& info) {
+    if (mPositionListenerDirty) {
+        mPositionListener = std::move(mStagingPositionListener);
+        mStagingPositionListener = nullptr;
+        mPositionListenerDirty = false;
+    }
+
     // Push the animators first so that setupStartValueIfNecessary() is called
     // before properties() is trampled by stagingProperties(), as they are
     // required by some animators.

libs/hwui/RenderNode.h

@@ -188,11 +188,9 @@ public:
         virtual void onPositionLost(RenderNode& node, const TreeInfo* info) = 0;
     };
 
-    // Note this is not thread safe, this needs to be called
-    // before the RenderNode is used for drawing.
-    // RenderNode takes ownership of the pointer
     ANDROID_API void setPositionListener(PositionListener* listener) {
-        mPositionListener = listener;
+        mStagingPositionListener = listener;
+        mPositionListenerDirty = true;
     }
 
     // This is only modified in MODE_FULL, so it can be safely accessed
@@ -275,6 +273,8 @@ private:
     // mDisplayList, not mStagingDisplayList.
     uint32_t mParentCount;
 
+    bool mPositionListenerDirty = false;
+    sp<PositionListener> mStagingPositionListener;
     sp<PositionListener> mPositionListener;
 
     UsageHint mUsageHint = UsageHint::Unknown;