Break a dependency of libui on libandroid

This was only a header dependency, but it still
created a circular dependency, which will cause
problems in another CL.

We fix this by creating a libarect static library
containing only that header. both libui and
libandroid now depend on it and reexport the 
header. 

We also make sure rect.h ends-up in the right
place.

Test: built and booted device
Bug: 35164655

Change-Id: Iba25b8b801b26b26ec1401c00caf367a06f197ca
diff --git a/include/gui/IGraphicBufferConsumer.h b/include/gui/IGraphicBufferConsumer.h
index dcddca4..60b7d24 100644
--- a/include/gui/IGraphicBufferConsumer.h
+++ b/include/gui/IGraphicBufferConsumer.h
@@ -25,8 +25,9 @@
 #include <utils/Timers.h>
 
 #include <binder/IInterface.h>
+
 #include <ui/PixelFormat.h>
-#include <ui/Rect.h>
+
 #include <gui/OccupancyTracker.h>
 
 #include <EGL/egl.h>