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

content/browser/power_profiler/power_profiler_service.cc

Index: content/browser/power_profiler/power_profiler_service.cc
diff --git a/content/browser/power_profiler/power_profiler_service.cc b/content/browser/power_profiler/power_profiler_service.cc
index 951034c3918125a81e45b7f18ab92bb12ea33596..0ba0d82710e1bd586db109a4ea993118d3a1136c 100644
--- a/content/browser/power_profiler/power_profiler_service.cc
+++ b/content/browser/power_profiler/power_profiler_service.cc
@@ -60,6 +60,9 @@ void PowerProfilerService::AddObserver(PowerProfilerObserver* observer) {
 }
 
 void PowerProfilerService::RemoveObserver(PowerProfilerObserver* observer) {
+  if (!observers_.might_have_observers())

[jam, 2014/06/19 16:42:34]

why is this needed?

[vivekg, 2014/06/19 17:46:02]

This was added after the discussion as per the
https://codereview.chromium.org/332623003/#msg24

[jam, 2014/06/20 05:59:46]

I don't follow that conversation, can you explained in a self-contained comment?

I'm looking at ObserverList::RemoveObserver code in
https://code.google.com/p/chromium/codesearch#chromium/src/base/observer_list...
and it doesn't assert that the given pointer is in the list.

+    return;
+
   observers_.RemoveObserver(observer);
 
   if (!observers_.might_have_observers())