Ok, here is a different approach at this change.

chrome/browser/extensions/extensions_service.h

Index: chrome/browser/extensions/extensions_service.h
diff --git a/chrome/browser/extensions/extensions_service.h b/chrome/browser/extensions/extensions_service.h
index 283d0dd981a7b38df0b488b6788887595120fba2..a7332ba3dc44595a3077c0fb90a15d2dfba3f9d8 100644
--- a/chrome/browser/extensions/extensions_service.h
+++ b/chrome/browser/extensions/extensions_service.h
@@ -252,6 +252,9 @@ class ExtensionsService
   // Handles sending notification that |extension| was unloaded.
   void NotifyExtensionUnloaded(Extension* extension);
 
+  // Helper that updates the active extension list used for crash reporting.
+  void UpdateActiveExtensionsInCrashReporter();
+
   // The profile this ExtensionsService is part of.
   Profile* profile_;