Added UMA collection for fullscreen / mouse lock bubble re-shows.

chrome/browser/ui/exclusive_access/exclusive_access_controller_base.cc

Index: chrome/browser/ui/exclusive_access/exclusive_access_controller_base.cc
diff --git a/chrome/browser/ui/exclusive_access/exclusive_access_controller_base.cc b/chrome/browser/ui/exclusive_access/exclusive_access_controller_base.cc
index 3559f376a678aa8b5671f2a8e86a92ff8d2964b1..473ec78830e91e959752c0721c5438eef69c9165 100644
--- a/chrome/browser/ui/exclusive_access/exclusive_access_controller_base.cc
+++ b/chrome/browser/ui/exclusive_access/exclusive_access_controller_base.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/ui/exclusive_access/exclusive_access_controller_base.h"
 
+#include "base/metrics/histogram_macros.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/exclusive_access/exclusive_access_manager.h"
@@ -16,8 +17,7 @@ using content::WebContents;
 
 ExclusiveAccessControllerBase::ExclusiveAccessControllerBase(
     ExclusiveAccessManager* manager)
-    : manager_(manager), tab_with_exclusive_access_(nullptr) {
-}
+    : manager_(manager) {}
 
 ExclusiveAccessControllerBase::~ExclusiveAccessControllerBase() {
 }
@@ -66,6 +66,23 @@ void ExclusiveAccessControllerBase::Observe(
     ExitExclusiveAccessIfNecessary();
 }
 
+void ExclusiveAccessControllerBase::BubbleReshown() {
+  ++bubble_reshow_count_;
+}
+
+void ExclusiveAccessControllerBase::Exiting() {
+  // Record the number of bubble reshows during this session. Only if simplified
+  // fullscreen is enabled.
+  if (ExclusiveAccessManager::IsSimplifiedFullscreenUIEnabled()) {
+    std::string histogram_name = "ExclusiveAccess.";
+    histogram_name += HistogramPrefix();
+    histogram_name += "BubbleReshowsPerSession";

[dominickn, 2016/02/23 00:05:27]

Nit: Please rename this to
ExclusiveAccess.BubbleReshowsPerSession.(Fullscreen|Mouselock) so that it's one
less concatenation here.

[Matt Giuca, 2016/02/23 02:50:28]

Done.

+    UMA_HISTOGRAM_COUNTS_100(histogram_name, bubble_reshow_count_);
+  }
+
+  bubble_reshow_count_ = 0;
+}
+
 void ExclusiveAccessControllerBase::SetTabWithExclusiveAccess(
     WebContents* tab) {
   // Tab should never be replaced with another tab, or