UMA data collection for docked windows

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 6a1961d47885f08227f44d481fd0415d107e8a0c..e0697cf8579605da134dbd619715f3ff8611d49a 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -216,6 +216,60 @@ other types of suffix sets.
   </summary>
 </histogram>
 
+<histogram name="Ash.Dock.Action" enum="DockedAction">
+  <summary>
+    User-initiated action taken that affects docked windows such as docking,
+    undocking, minimizing, restoring, closing or just dragging a docked window.
+  </summary>
+</histogram>
+
+<histogram name="Ash.Dock.ActionSource" enum="DockedActionSource">
+  <summary>
+    Source (mouse, touch or unknown) of the user-initiated action for docked
+    windows.
+  </summary>
+</histogram>
+
+<histogram name="Ash.Dock.ItemsAll">
+  <summary>
+    Number of all docked windows or panels including hidden or minimized.
+    Recorded on every user action.

[Ilya Sherman, 2013/11/04 23:31:50]

On every user action that interacts with docked windows?  Or just on every user
action ever?  (Please document in the histogram <summary>, not on the codereview
site.)

[varkha, 2013/11/05 17:41:15]

Done.

+  </summary>
+</histogram>
+
+<histogram name="Ash.Dock.ItemsLarge">
+  <summary>
+    Number of large (wider than dock maximum width) windows that had to be
+    shrunk to get docked among the visible docked windows. Recorded on every
+    user action.
+  </summary>
+</histogram>
+
+<histogram name="Ash.Dock.ItemsPanels">
+  <summary>
+    Number of docked visible panels. Recorded on every user action.
+  </summary>
+</histogram>
+
+<histogram name="Ash.Dock.ItemsVisible">
+  <summary>
+    Number of visible docked windows or panels. Recorded on every user action.
+  </summary>
+</histogram>
+
+<histogram name="Ash.Dock.TimeBetweenUse" units="seconds">

[Ilya Sherman, 2013/11/04 23:31:50]

If you use UMA_HISTOGRAM_CUSTOM_TIMES, I'm pretty sure the values will be
emitted as milliseconds.  If you want to emit seconds, then you'll need to use
UMA_HISTOGRAM_CUSTOM_COUNTS instead, and call TimeDelta::ToSeconds() yourself.

[varkha, 2013/11/05 17:41:15]

Done.

+  <summary>
+    The amount of time between instances of docking, undocking a window or any
+    other action affecting docked state.
+  </summary>
+</histogram>
+
+<histogram name="Ash.Dock.Width" units="pixels">
+  <summary>
+    Width of the docked area in pixels. Recorded every time it changes.

[Ilya Sherman, 2013/11/04 23:31:50]

Just to sanity check: If I drag-resize the area, how many times will the size be
emitted to this histogram as a result of that drag?  Hopefully just once?

[varkha, 2013/11/05 17:41:15]

Just once when a docked window resize is complete (on mouse release) and only if
the width actually changes. I've tried to clarify that in summary.

+  </summary>
+</histogram>
+
 <histogram name="Ash.GestureCreated" enum="UIEventType">
   <summary>
     The gesture-events recognized and dispatched by the browser gesture
@@ -20667,6 +20721,25 @@ other types of suffix sets.
   </int>
 </enum>
 
+<enum name="DockedAction" type="int">
+  <int value="0" label="NONE"/>
+  <int value="1" label="DOCK"/>
+  <int value="2" label="UNDOCK"/>
+  <int value="3" label="RESIZE"/>
+  <int value="4" label="REORDER"/>
+  <int value="5" label="EVICT"/>
+  <int value="6" label="MAXIMIZE"/>
+  <int value="7" label="MINIMIZE"/>
+  <int value="8" label="RESTORE"/>
+  <int value="9" label="CLOSE"/>

[Ilya Sherman, 2013/11/04 23:31:50]

nit: These are human-visible strings on the dashboard, so "Close" is probably
better than "CLOSE".

[varkha, 2013/11/05 17:41:15]

Done.

+</enum>
+
+<enum name="DockedActionSource" type="int">
+  <int value="0" label="UNKNOWN"/>
+  <int value="1" label="MOUSE"/>
+  <int value="2" label="TOUCH"/>
+</enum>
+
 <enum name="DomainBoundCerts.GetCertResult" type="int">
   <int value="0" label="SYNC_SUCCESS"/>
   <int value="1" label="ASYNC_SUCCESS"/>