DisplayList draw operation reordering

bug:8037003

The reordering enables similar operations to draw together, minimizing the
OpenGL state change operations that go inbetween draws. Eventually, multiple
complete canvas draw operations will be merged (into a single glDrawArrays call,
for example)

Reorders DisplayList draw operations when:

-They can move backwards in the command stream to be after similar
operations without violating draw ordering

-The OpenGLRenderer is in a simple, replayable state (no complex clip,
or filter/shadow etc)

Also adds two system properties to control the deferral/reordering:
    "debug.hwui.disable_draw_defer"
    "debug.hwui.disable_draw_reorder"
which can be set to "true" to control the display list manipulation

Change-Id: I5e89f3cb0ea2d2afd3e15c64d7f32b8406777a32