BufferHelperPointerVector -> BufferHelperQueue (deque) DynamicBuffer.mBufferFreeList is a vector<unique_ptr>. DynamicBuffer::allocate erases an element from the front, which is what deque is exactly good for. Changed other uses too (mBufferFreeList, VertexArrayVk.mCachedStreamIndexBuffers) per Charlie's recommendation. Yields a significant power improvement in words_crush trace. Bug: b/302020992 Change-Id: I1b0242481404b8fc2cfdc27611252308b922f4d7 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/4886367 Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Commit-Queue: Roman Lavrov <romanl@google.com>