Record user actions for long-press follow-on actions.

ui/touch_selection/touch_selection_controller.cc

Index: ui/touch_selection/touch_selection_controller.cc
diff --git a/ui/touch_selection/touch_selection_controller.cc b/ui/touch_selection/touch_selection_controller.cc
index 230942f6f7f3a2163791a64d2837ec3bbf984c0e..e4dcb7e71d742e5df999427ea95cb82a3671cdc2 100644
--- a/ui/touch_selection/touch_selection_controller.cc
+++ b/ui/touch_selection/touch_selection_controller.cc
@@ -7,6 +7,7 @@
 #include "base/auto_reset.h"
 #include "base/logging.h"
 #include "base/metrics/histogram_macros.h"
+#include "base/metrics/user_metrics.h"
 
 namespace ui {
 namespace {
@@ -384,6 +385,10 @@ void TouchSelectionController::OnDragBegin(
   if (anchor_drag_to_selection_start_)
     std::swap(base, extent);
 
+  // If this is the first drag, log an action to allow user action sequencing.
+  if (!selection_handle_dragged_) {
+    base::RecordAction(base::UserMetricsAction("MobileSelectionChanged"));

[mohsen, 2016/05/12 17:27:44]

nit: By "Mobile" do you mean Android? Can we use a more general name that is
also meaningful on desktop?

nit2: Curly braces are not necessary here.

[Donn Denman, 2016/05/12 17:37:46]

Good point -- changed to SelectionChanged.
Done.

+  }
   selection_handle_dragged_ = true;
 
   // When moving the handle we want to move only the extent point. Before doing