Adding onFrameAvailable test for BLASTBufferQueue

Bug: 142546708
Test: build, boot, libgui_test
Change-Id: I92a03e777334b7b4729338c7e3a75dad1db8b613
diff --git a/libs/gui/BLASTBufferQueue.cpp b/libs/gui/BLASTBufferQueue.cpp
index 3a369cd..9a50175 100644
--- a/libs/gui/BLASTBufferQueue.cpp
+++ b/libs/gui/BLASTBufferQueue.cpp
@@ -64,7 +64,7 @@
                                                    : Fence::NO_FENCE);
         mNextCallbackBufferItem = BufferItem();
     }
-    mDequeueWaitCV.notify_one();
+    mDequeueWaitCV.notify_all();
     decStrong((void*)transactionCallbackThunk);
 }