egl: Reintroduce eglGetRenderBufferANDROID

eglGetRenderBufferANDROID was removed as it had no users. This commit
reintroduces this extensions as it's used by Qualcomm graphics HAL.

Change-Id: I493306830a0d4f8722a42bcc84fb49236afdabeb

Conflicts:
	opengl/libs/EGL/eglApi.cpp
BufferQueue: Increase MIN_UNDEQUEUED from 2 to 3.

If 2 queueBuffers happen fairly closely, the former buffer is not picked by
display. But SurfaceTexture won't return this to clients, since its not the
oldest. It will return the locked buffer causing deadlock.

Increasing the min_dequeued buffer count to 3 (from 2) will increase the
distance between video and display by 1 more.

CRs-fixed: 382393

Change-Id: I275c01473c7057714da35693dfda7a358e9d9285
frameworks/native: Increase EGL blob cache size limits (adapted from mr0 branch)

Increase the size of the EGL Blob Cache to 2MB and the key size to 4K.
This helps improve the performance of OpenGL apps, especially Open GLESv1.1
apps whose shaders are generated on the fly.

CRs-fixed: 393074

Change-Id: Ic3772a9722b63351c940d40794cf54073a8b5eed