Fix ALL compile warnings

 All warnings/errors fixed for GCC & Clang

Change-Id: I2ece3a136a5ae97a9acc3069537ed986238b5fd3
diff --git a/libs/hwui/RenderNode.cpp b/libs/hwui/RenderNode.cpp
index 3eb779f..b77b36f 100644
--- a/libs/hwui/RenderNode.cpp
+++ b/libs/hwui/RenderNode.cpp
@@ -836,7 +836,8 @@
             DisplayListLogBuffer& logBuffer = DisplayListLogBuffer::getInstance();
             const int saveCountOffset = renderer.getSaveCount() - 1;
             const int projectionReceiveIndex = mDisplayListData->projectionReceiveIndex;
-            for (unsigned int i = 0; i < mDisplayListData->displayListOps.size(); i++) {
+            const int size = static_cast<int>(mDisplayListData->displayListOps.size());
+            for (int i = 0; i < size; i++) {
                 DisplayListOp *op = mDisplayListData->displayListOps[i];
 
 #if DEBUG_DISPLAY_LIST