Fix double create of Caches

bug:19208182
Change-Id: I91ac591cecc207da1b102013ca4985dd075cca80
diff --git a/libs/hwui/renderstate/RenderState.cpp b/libs/hwui/renderstate/RenderState.cpp
index e4c8745..c839718 100644
--- a/libs/hwui/renderstate/RenderState.cpp
+++ b/libs/hwui/renderstate/RenderState.cpp
@@ -46,7 +46,9 @@
     mStencil = new Stencil();
 
     // This is delayed because the first access of Caches makes GL calls
-    mCaches = &Caches::createInstance(*this);
+    if (!mCaches) {
+        mCaches = &Caches::createInstance(*this);
+    }
     mCaches->init();
     mCaches->textureCache.setAssetAtlas(&mAssetAtlas);
 }