Disable GPU process unless EGL backend is used.
Disable GPU process unless EGL backend is used.

TOUCH_UI relies on EGLImage transport from the GPU process to the browser. If Chrome is launched without the --use-gl=egl flag on this build, refuse to start the GPU process.

BUG=none
TEST=start a TOUCH_UI build of chrome with --use-gl=desktop and go to 3D css page; no GPU process should start

Review URL: http://codereview.chromium.org/7273011

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@90756 0039d316-1c4b-4281-b951-d872f2087c98

yitian134/chromium,ropik/chromium,gavinp/chromium,adobe/chromium,adobe/chromium,gavinp/chromium,yitian134/chromium,ropik/chromium,ropik/chromium,adobe/chromium,yitian134/chromium,gavinp/chromium,adobe/chromium,adobe/chromium,gavinp/chromium,gavinp/chromium,adobe/chromium,gavinp/chromium,ropik/chromium,yitian134/chromium,ropik/chromium,adobe/chromium,yitian134/chromium,adobe/chromium,yitian134/chromium,adobe/chromium,yitian134/chromium,yitian134/chromium,yitian134/chromium,adobe/chromium,adobe/chromium,ropik/chromium,gavinp/chromium,gavinp/chromium,ropik/chromium,ropik/chromium,ropik/chromium,gavinp/chromium,yitian134/chromium,gavinp/chromium