Bug 903722 - Only demote to a software canvas if we're a GL-backed Skia canvas r=bjacob
Back out 4537337759b7 (bug 910517) because nobody expects the talos inquisition

--HG--
rename : content/canvas/src/WebGLMemoryReporterWrapper.h => content/canvas/src/WebGLMemoryMultiReporterWrapper.h