[ImportantSites] Adding usage metrics.

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index 83c8ef36c5e7a13cc4c6ac0b73c2ab2911b772d6..5508bc26d10f3006d1b4cdfd4d1fda944e77f7fe 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -17521,6 +17521,34 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="History.ClearBrowsingData.ImportantDialogShown"
+    enum="BooleanShown">
+  <owner>dmurph@chromium.org</owner>
+  <summary>
+    Recorded when the user presses the 'clear' button in the Clear Browsing

[Theresa, 2016/06/27 20:37:53]

nit: clear browsing data dialog?

[dmurph, 2016/06/28 22:01:41]

Done.

+    Dialog. We record 'true' when the important sites dialog is shown.
+  </summary>
+</histogram>
+
+<histogram name="History.ClearBrowsingData.NumImportant">

[Theresa, 2016/06/27 20:37:53]

Should this be NumImportantDeselected?

[dmurph, 2016/06/28 22:01:41]

Yes, thanks.

+  <owner>dmurph@chromium.org</owner>
+  <summary>
+    Recorded when the user presses the 'clear' button when presented with the
+    list of important sites they might want to exclude from clearing browsing
+    data. We record the number of sites the user deselected, or protected, from
+    clearing.
+  </summary>
+</histogram>
+
+<histogram name="History.ClearBrowsingData.OnCreate" enum="Boolean">
+  <owner>dmurph@chromium.org</owner>
+  <summary>
+    Recorded when the Clear Browsing Data screen is created on Android. We
+    record 'true' when the screen is started fresh, and 'false' when the screen
+    is deserialized (resumed) from the background.

[Theresa, 2016/06/27 20:37:53]

Out of curiosity, what are we going to use this metric for?

[dmurph, 2016/06/28 22:01:41]

Changed to a user action.

+  </summary>
+</histogram>
+
 <histogram
     name="History.ClearBrowsingData.PasswordsDeletion.AdditionalDatatypesCount">
   <owner>msramek@chromium.org</owner>
@@ -54800,6 +54828,31 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="Storage.AndroidManage.Button" enum="AndroidManageSpaceButton">

[Theresa, 2016/06/27 20:37:53]

nit: ActionTaken seems like a better name than Button.

[dmurph, 2016/06/28 22:01:41]

Done.

[dmurph, 2016/06/28 22:01:41]

Done.

+  <owner>dmurph@chromium.org</owner>
+  <summary>
+    Recorded when the user presses a button in the 'Manage Space' screen for
+    Chrome. Note: the 'Clear App Data' option is likely incorrect, as the result
+    of that button disables UMA recording (as we factory reset the app).

[Theresa, 2016/06/27 20:37:53]

Is there a way we can get an idea of how many users clear app data vs take one
of the other actions? Maybe we can ask UMA folks if there's a way to force an
upload before data is cleared?

If not, we can brainstorm some other options.

[dmurph, 2016/06/28 22:01:41]

Since the app reset logic is part of the OS itself, we would probably have to
block until the histogram is uploaded. Since we're not directly looking for this
metric right now, I'm fine with punting this problem till later.

+  </summary>
+</histogram>
+
+<histogram name="Storage.AndroidManage.ProcessInitSuccess" enum="Boolean">
+  <owner>dmurph@chromium.org</owner>
+  <summary>
+    Recorded when the ManageSpace UI is shown to the user. We record whether the
+    browser process initializing was successful.
+  </summary>
+</histogram>
+
+<histogram name="Storage.AndroidStorageSettings.Clear" enum="Boolean">
+  <owner>dmurph@chromium.org</owner>
+  <summary>
+    Recorded when the user presses 'clear' in the 'storage' site category
+    preferences.
+  </summary>
+</histogram>
+
 <histogram name="Storage.Blob.Broken" enum="BooleanBroken">
   <owner>dmurph@chromium.org</owner>
   <summary>
@@ -64592,6 +64645,12 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="262154" label="4.10"/>
 </enum>
 
+<enum name="AndroidManageSpaceButton" type="int">
+  <int value="0" label="Clear Unimportant Storage"/>
+  <int value="1" label="Manage Site Storage"/>
+  <int value="2" label="Clear App Data"/>
+</enum>
+
 <enum name="AndroidMemoryNotificationBackground" type="int">
   <int value="0" label="TrimMemoryUiHidden"/>
   <int value="1" label="TrimMemoryBackground"/>