Refactor GLES20Canvas/HardwareRenderer JNI layers

GLES20Canvas defined several JNI functions used only by HardwareRenderer.
Now that we have a JNI layer dedicated to HardwareRenderer we should
host the renderer related methods there.

Change-Id: I0bcb4ad0bcc1c4a37290df10c1685f2cfe5504ca
4 files changed