Disable force-compositing-mode on MacOSX earlier than 10.8

content/browser/gpu/software_rendering_list.json

Index: content/browser/gpu/software_rendering_list.json
===================================================================
--- content/browser/gpu/software_rendering_list.json	(revision 181512)
+++ content/browser/gpu/software_rendering_list.json	(working copy)
@@ -75,7 +75,7 @@
 {
   "name": "software rendering list",
   // Please update the version number whenever you change this file.
-  "version": "4.14",
+  "version": "4.15",
   "entries": [
     {
       "id": 1,
@@ -990,6 +990,21 @@
       "blacklist": [
         "force_compositing_mode"
       ]
+    },
+    {
+      "id": 66,
+      "description": "Force compositing mode is unstable in MacOSX earlier than 10.8.",
+      "cr_bugs": [174101],
+      "os": {
+        "type": "macosx",
+        "version": {
+          "op": "<",
+          "number": "10.8"
+        }
+      },
+      "blacklist": [
+        "force_compositing_mode"
+      ]
     }
   ]
 }