[DevTools] [PowerProfiler] Fix for browser crash with active timeline recording for capturing power.

content/browser/power_profiler/power_profiler_service.h

Index: content/browser/power_profiler/power_profiler_service.h
diff --git a/content/browser/power_profiler/power_profiler_service.h b/content/browser/power_profiler/power_profiler_service.h
index 35f2f65cce3f467f0cbe07175201e990b7d71ed6..d519fe52c9dcc4abada8378b32b06dd2e4897820 100644
--- a/content/browser/power_profiler/power_profiler_service.h
+++ b/content/browser/power_profiler/power_profiler_service.h
@@ -24,6 +24,9 @@ class CONTENT_EXPORT PowerProfilerService {
   // Add and remove an observer.
   void AddObserver(PowerProfilerObserver* observer);
   void RemoveObserver(PowerProfilerObserver* observer);
+  bool HasObserver(PowerProfilerObserver* observer) const {
+    return observers_.HasObserver(observer);
+  }
 
   bool IsAvailable();