DO NOT MERGE rs: Stop using IGBC::BufferItem

Switches all uses of IGraphicBufferConsumer::BufferItem (and
BufferQueue::BufferItem) to the BufferItem in libgui. Depends on
frameworks/native I699ed0a6837076867ca756b28d1ffb2238f7a0d9.

Cherry-pick of I187b3a7d05196b6289596afac8fb9a9d4aebff76

Change-Id: I437b437e333e2ded1b96af8c0426996d340b1507
diff --git a/rsGrallocConsumer.cpp b/rsGrallocConsumer.cpp
index 2d57421..f19f171 100644
--- a/rsGrallocConsumer.cpp
+++ b/rsGrallocConsumer.cpp
@@ -24,6 +24,7 @@
 #include <cutils/compiler.h>
 #include <utils/Log.h>
 #include "rsGrallocConsumer.h"
+#include <gui/BufferItem.h>
 #include <ui/GraphicBuffer.h>
 
 
@@ -69,7 +70,7 @@
         }
     }
 
-    BufferQueue::BufferItem b;
+    BufferItem b;
 
     err = acquireBufferLocked(&b, 0);
     if (err != OK) {