mobile/app: need to create an XColormap in X11 implementation
mobile/app: need to create an XColormap in X11 implementation

When the preferred visual returned by EGL is different from the parent
window's visual, a private colormap is needed in the call to
XCreateWindow. See X server source code
http://cgit.freedesktop.org/xorg/xserver/tree/dix/window.c#n708

This patch systematically creates a TrueColor XColormap, regardless of
the visual returned by eglGetConfigAttrib().

Fixes #9997

Change-Id: I3caf7c6d46991b1f0268e72197fca5186612b5da
Reviewed-on: https://go-review.googlesource.com/6260
Reviewed-by: David Crawshaw <a2f0bf29257797dd66800b4fbb9945c3e216c004@golang.org>
Reviewed-by: Nigel Tao <58ae08b3356928ff9c67562b4719487d54fe8348@golang.org>

goldcaddy77/mobile,qskycolor/mobile,samanalysis/mobile,b54898533/mobile,lonphy23t/mobile,b54898533/mobile,MaxCy330/mobile,freeman0211/mobile,MaxCy330/mobile,golang/mobile,ichu501/mobile,0x90sled/mobile,zach-klippenstein/mobile,MaxCy330/mobile,qskycolor/mobile,steeve/mobile,MaxCy330/mobile,cainiaocome/mobile,samanalysis/mobile,cainiaocome/mobile,xing/gomobile,cainiaocome/mobile,0x90sled/mobile,zach-klippenstein/mobile,swisspol/mobile,samanalysis/mobile,qskycolor/mobile,DanielWorld/mobile,xing/gomobile,b54898533/mobile,ppamorim/mobile,freeman0211/mobile,qskycolor/mobile,steeve/mobile,zach-klippenstein/mobile,cainiaocome/mobile,lonphy23t/mobile,samanalysis/mobile,zach-klippenstein/mobile,ichu501/mobile,golang/mobile,tempbottle/mobile,lonphy23t/mobile,tempbottle/mobile,goldcaddy77/mobile,ichu501/mobile,goldcaddy77/mobile,tempbottle/mobile,DanielWorld/mobile,ppamorim/mobile,swisspol/mobile,swisspol/mobile,swisspol/mobile,goldcaddy77/mobile,xing/gomobile,DanielWorld/mobile,ppamorim/mobile,swisspol/mobile,xing/gomobile,goldcaddy77/mobile,ppamorim/mobile,lonphy23t/mobile,steeve/mobile,MaxCy330/mobile,0x90sled/mobile,lonphy23t/mobile,steeve/mobile,ichu501/mobile,DanielWorld/mobile,tempbottle/mobile,b54898533/mobile,ppamorim/mobile,cainiaocome/mobile,b54898533/mobile,ichu501/mobile,xing/gomobile,golang/mobile,freeman0211/mobile,freeman0211/mobile,0x90sled/mobile,0x90sled/mobile,golang/mobile,samanalysis/mobile,tempbottle/mobile