allow re-targetting of surfaces

Surfaces can now be parcelized and sent to remote
processes. When a surface crosses a process
boundary, it looses its connection with the
current process and gets attached to the new one.

Change-Id: I39c7b055bcd3ea1162ef2718d3d4b866bf7c81c0
diff --git a/libs/ui/GraphicBuffer.cpp b/libs/ui/GraphicBuffer.cpp
index 3ddde38..4b5f025 100644
--- a/libs/ui/GraphicBuffer.cpp
+++ b/libs/ui/GraphicBuffer.cpp
@@ -111,6 +111,9 @@
     if (mOwner != ownData)
         return INVALID_OPERATION;
 
+    if (handle && w==width && h==height && f==format && reqUsage==usage)
+        return NO_ERROR;
+
     if (handle) {
         GraphicBufferAllocator& allocator(GraphicBufferAllocator::get());
         allocator.free(handle);