C2VdaBqBlockPool: close handle from C2AllocatorGralloc

At ag/13824423 we fixed the description of
WrapNativeCodec2GrallocHandle() that the returned handle should be
closed. This CL closes the handle if the ownership is not transfered
to C2GrallocAllocation via priorGraphicAllocation() call.

Bug: 181541291
Test: android.media.cts.AdaptivePlaybackTest

Change-Id: Ifbe842f715977f4f6f79dfd2b33efbee9c0d1191

plugin_store/C2VdaBqBlockPool.cpp

@@ -90,6 +90,7 @@ std::shared_ptr<C2GraphicAllocation> ConvertGraphicBuffer2C2Allocation(
     const auto err = allocator->priorGraphicAllocation(c2Handle, &allocation);
     if (err != C2_OK) {
         ALOGE("C2Allocator::priorGraphicAllocation() failed: %d", err);
+        native_handle_close(c2Handle);
         native_handle_delete(c2Handle);
         return nullptr;
     }