Fix a few issues with NATIVE_WINDOW_TRANSFORM_HINT

- fixed uninitialized variable
- set hint to indentity when transform is too complex
- make sure FrameBufferNativeWindow doesn't fail on needed perform commands

Bug: 4487161
Change-Id: I7cb2b0869b72404732eca7cb2d145ff669e2ed9b
diff --git a/libs/gui/SurfaceTextureClient.cpp b/libs/gui/SurfaceTextureClient.cpp
index 1dc6cd2..986fc7e 100644
--- a/libs/gui/SurfaceTextureClient.cpp
+++ b/libs/gui/SurfaceTextureClient.cpp
@@ -55,6 +55,9 @@
     mQueryWidth = 0;
     mQueryHeight = 0;
     mQueryFormat = 0;
+    mDefaultWidth = 0;
+    mDefaultHeight = 0;
+    mTransformHint = 0;
     mConnectedToCpu = false;
 }