Enabled cropping support in SurfaceTexture

SurfaceTexture will modify the crop rect so it matches
the desired output aspect ratio when the scaling
mode is NATIVE_WINDOW_SCALING_MODE_CROP.  Added a test
for this new scaling mode.

Change-Id: I60f24dcbc294b65cd10a393d9e27d40f07d27bb6
diff --git a/libs/gui/SurfaceTextureClient.cpp b/libs/gui/SurfaceTextureClient.cpp
index aa114ed..99c025f 100644
--- a/libs/gui/SurfaceTextureClient.cpp
+++ b/libs/gui/SurfaceTextureClient.cpp
@@ -555,6 +555,7 @@
     switch (mode) {
         case NATIVE_WINDOW_SCALING_MODE_FREEZE:
         case NATIVE_WINDOW_SCALING_MODE_SCALE_TO_WINDOW:
+        case NATIVE_WINDOW_SCALING_MODE_SCALE_CROP:
             break;
         default:
             ALOGE("unknown scaling mode: %d", mode);