Bug 892910: Deal with newSize becoming empty in CreatePartialBitmapForSurface. r=BenWa

This patch deals with the situation where newSize becomes empty and causes a division by 0 in the current code. It also ensures all the callers will abort any potential drawing when CreatePartialBitmapForSurface returns a nullptr.
Bug 1088831 - Count storebuffer overflows, account for minor GCs, and implement timed regions, r=jonco

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extra : rebase_source : 45985b1dd8f4ee69ea992bdbd1b25746bfb17ffd