move lock/unlock implementaion outside of Surface into SurfaceTextureClient

This makes ANativeWindow_lock/ANativeWindow_unlockAndPost work
with ANativeWindows implemented by Surface and SurfaceTextureClient.

Also, Surface now inherits directly from SurfaceTextureClient.

Bug: 5003724
Change-Id: I9f285877c7bae9a262e9a7af91c2bae78804b2ef
diff --git a/native/include/android/native_window.h b/native/include/android/native_window.h
index 337fa96..2f4f2d3 100644
--- a/native/include/android/native_window.h
+++ b/native/include/android/native_window.h
@@ -99,10 +99,16 @@
  * width and height must be either both zero or both non-zero.
  *
  */
-int32_t ANativeWindow_setBuffersGeometry(ANativeWindow* window, int32_t width, int32_t height, int32_t format);
+int32_t ANativeWindow_setBuffersGeometry(ANativeWindow* window,
+        int32_t width, int32_t height, int32_t format);
 
 /**
  * Lock the window's next drawing surface for writing.
+ * inOutDirtyBounds is used as an in/out parameter, upon entering the
+ * function, it contains the dirty region, that is, the region the caller
+ * intends to redraw. When the function returns, inOutDirtyBounds is updated
+ * with the actual area the caller needs to redraw -- this region is often
+ * extended by ANativeWindow_lock.
  */
 int32_t ANativeWindow_lock(ANativeWindow* window, ANativeWindow_Buffer* outBuffer,
         ARect* inOutDirtyBounds);