[DevTools] Add power profiler and power overview in timeline panel.

Source/devtools/front_end/SettingsScreen.js

Index: Source/devtools/front_end/SettingsScreen.js
diff --git a/Source/devtools/front_end/SettingsScreen.js b/Source/devtools/front_end/SettingsScreen.js
old mode 100644
new mode 100755
index 44b78b671beb1569cb867dec912f330cbd006ced..87aaa9b471f4c89567c12f127209984cc5db6510
--- a/Source/devtools/front_end/SettingsScreen.js
+++ b/Source/devtools/front_end/SettingsScreen.js
@@ -701,6 +701,18 @@ WebInspector.ExperimentsSettingsTab.prototype = {
         input.type = "checkbox";
         input.name = experiment.name;
         input.checked = experiment.isEnabled();
+
+        if (experiment.name === "powerProfile") {

[pfeldman, 2014/01/09 11:38:52]

This seems wrong - generic method should not be concrete experiment-aware.

+            function powerProfileStatusCallback(event) {
+                if (event.data)
+                    return;
+                input.disabled = true;
+                experiment.setEnabled(false);
+            }
+            WebInspector.powerProfiler.addEventListener(WebInspector.PowerProfiler.EventTypes.PowerProfileSupportStatus, powerProfileStatusCallback);
+            WebInspector.powerProfiler.checkStatus();

[pfeldman, 2014/01/09 11:38:52]

You should allow enabling this experiment unconditionally.

+        }
+
         function listener()
         {
             experiment.setEnabled(input.checked);