Backed out changeset 97a3a6e6550b (bug 1356448) for frequently failing xpcshell's test_ChildScalars.js and test_ChildHistograms.js on Windows 7 VM debug. r=backout a=merge

MozReview-Commit-ID: CuDON8yOGQv

--HG--
extra : source : 67bcd1fe0009aee013bd350a00b1e50a3ea05c05

modules/libpref/init/all.js

@@ -4637,9 +4637,6 @@ pref("layers.bench.enabled", false);
 pref("layers.gpu-process.enabled", true);
 pref("layers.gpu-process.max_restarts", 3);
 pref("media.gpu-process-decoder", true);
-#ifdef NIGHTLY_BUILD
-pref("layers.gpu-process.allow-software", true);
-#endif
 #endif
 
 // Whether to force acceleration on, ignoring blacklists.