Bug 1348273 - Convert crash annotations into a machine-readable list of constants; r=ted.mielczarek,njn,dholbert,mak,cpearce,mcmanus,froydnj,Dexter,jrmuizel,jchen,jimm,bz,surkov

This introduces the machinery needed to generate crash annotations from a YAML
file. The relevant C++ functions are updated to take a typed enum. JavaScript
calls are unaffected but they will throw if the string argument does not
correspond to one of the known entries in the C++ enum. The existing whitelists
and blacklists of annotations are also generated from the YAML file and all
duplicate code related to them has been consolidated. Once written out to the
.extra file the annotations are converted in string form and are no different
than the existing ones.

All existing annotations have been included in the list (and some obsolete ones
have been removed) and all call sites have been updated including tests where
appropriate.

docshell/base/nsDocShell.cpp

@@ -1700,8 +1700,8 @@ NS_IMETHODIMP
 nsDocShell::SetRemoteTabs(bool aUseRemoteTabs)
 {
   if (aUseRemoteTabs) {
-    CrashReporter::AnnotateCrashReport(NS_LITERAL_CSTRING("DOMIPCEnabled"),
-                                       NS_LITERAL_CSTRING("1"));
+    CrashReporter::AnnotateCrashReport(CrashReporter::Annotation::DOMIPCEnabled,
+                                       true);
   }
 
   mUseRemoteTabs = aUseRemoteTabs;