Reduce emulator logspam

The emulator doesn't support systrace, but we should point that out
at most once per process.

Bug 7436352

Change-Id: I30e0094dc3b24bc3ab6bc2799ce81ca0a6bb7d9d
load non opengles wallpapers for platforms without hardware graphics

Platforms without a hardware graphics, frequently get
"Unfortunately, System UI Crashed" pop-up message on boot-up, which
is due to an Android Runtime Exception
"java.lang.RuntimeException: eglConfig not initialized" when SystemUI
fail to load OpenGLES wallpapers.

This patch make sure that Android runtime checks for GPU availability
(by checking a build time property "ro.nohardwaregfx") before loading
opengles wallpapers.

Change-Id: I1d5a37ff129cdd01c3f98b0cebb54d55469206d2