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

chrome/browser/ui/exclusive_access/fullscreen_controller_state_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/command_line.h"
+#include "base/test/histogram_tester.h"
 #include "build/build_config.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_tabstrip.h"
 #include "chrome/browser/ui/exclusive_access/exclusive_access_context.h"
 #include "chrome/browser/ui/exclusive_access/fullscreen_controller.h"
 #include "chrome/browser/ui/exclusive_access/fullscreen_controller_state_test.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/test/base/browser_with_test_window_test.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/url_constants.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 // The FullscreenControllerStateUnitTest unit test suite exhastively tests
 // the FullscreenController through all permutations of events. The behavior
 // of the BrowserWindow is mocked via FullscreenControllerTestWindow.
 
+namespace {
+
+const char kFullscreenReshowHistogramName[] =
+    "ExclusiveAccess.FullscreenBubbleReshowsPerSession";
 
 // FullscreenControllerTestWindow ----------------------------------------------
 
 // A BrowserWindow used for testing FullscreenController. The behavior of this
 // mock is verfied manually by running FullscreenControllerStateInteractiveTest.
 class FullscreenControllerTestWindow : public TestBrowserWindow,
                                        ExclusiveAccessContext {
  public:
   // Simulate the window state with an enumeration.
   enum WindowState {
@@ skipping 206 matching lines @@
 void FullscreenControllerTestWindow::HideDownloadShelf() {
   GetDownloadShelf()->Hide();
 }
 
 void FullscreenControllerTestWindow::UpdateExclusiveAccessExitBubbleContent(
     const GURL& url,
     ExclusiveAccessBubbleType bubble_type) {}
 
 void FullscreenControllerTestWindow::OnExclusiveAccessUserInput() {}
 
+}  // namespace
+
 // FullscreenControllerStateUnitTest -------------------------------------------
 
 // Unit test fixture testing Fullscreen Controller through its states. Most of
 // the test logic comes from FullscreenControllerStateTest.
 class FullscreenControllerStateUnitTest : public BrowserWithTestWindowTest,
                                           public FullscreenControllerStateTest {
  public:
   FullscreenControllerStateUnitTest();
 
   // FullscreenControllerStateTest:
@@ skipping 208 matching lines @@
   window_->ExitFullscreen();
   ChangeWindowFullscreenState();
   EXPECT_EQ(EXCLUSIVE_ACCESS_BUBBLE_TYPE_NONE,
             browser()
                 ->exclusive_access_manager()
                 ->GetExclusiveAccessExitBubbleType());
 }
 
 // Test that switching tabs takes the browser out of tab fullscreen.
 TEST_F(FullscreenControllerStateUnitTest, ExitTabFullscreenViaSwitchingTab) {
+  base::HistogramTester histogram_tester;
+
   AddTab(browser(), GURL(url::kAboutBlankURL));
   AddTab(browser(), GURL(url::kAboutBlankURL));
   ASSERT_TRUE(InvokeEvent(TAB_FULLSCREEN_TRUE));
   ASSERT_TRUE(InvokeEvent(WINDOW_CHANGE));
   ASSERT_TRUE(browser()->window()->IsFullscreen());
+  histogram_tester.ExpectTotalCount(kFullscreenReshowHistogramName, 0);
 
   browser()->tab_strip_model()->SelectNextTab();
   ChangeWindowFullscreenState();
   EXPECT_FALSE(browser()->window()->IsFullscreen());
+
+  // Do a simple test that histograms are being recorded upon exiting the
+  // fullscreen session.
+  histogram_tester.ExpectUniqueSample(kFullscreenReshowHistogramName, 0, 1);

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

Nit: is there a test that reshows the bubble so you can check samples go into
the histogram? Or can you add a test that manually triggers the bubble?

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

No, there isn't. I tried writing some minimal tests yesterday but I think we
just need to start a brand new unit test from scratch.

These "unit tests" are extremely heavyweight and involve spinning up a browser
window. I would have to simulate mouse movements, timers, etc. I don't really
want to add more of these. I just want a simple unit test around
FullscreenController, but there isn't one.

At least for now this shows that we record to the histogram. I plan to add
comprehensive unit tests for the exclusive access classes in the future, and
this will be included there.

[dominickn, 2016/02/23 03:05:53]

Acknowledged.

 }
 
 // Test that switching tabs via detaching the active tab (which is in tab
 // fullscreen) takes the browser out of tab fullscreen. This case can
 // occur if the user is in both tab fullscreen and immersive browser fullscreen.
 TEST_F(FullscreenControllerStateUnitTest, ExitTabFullscreenViaDetachingTab) {
   AddTab(browser(), GURL(url::kAboutBlankURL));
   AddTab(browser(), GURL(url::kAboutBlankURL));
   ASSERT_TRUE(InvokeEvent(TAB_FULLSCREEN_TRUE));
   ASSERT_TRUE(InvokeEvent(WINDOW_CHANGE));
@@ skipping 389 matching lines @@
   EXPECT_FALSE(wc_delegate->IsFullscreenForTabOrPending(tab));
   EXPECT_FALSE(second_wc_delegate->IsFullscreenForTabOrPending(tab));
   EXPECT_FALSE(GetFullscreenController()->IsWindowFullscreenForTabOrPending());
   EXPECT_FALSE(second_browser->exclusive_access_manager()
                    ->fullscreen_controller()
                    ->IsWindowFullscreenForTabOrPending());
 
   // Required tear-down specific to this test.
   second_browser->tab_strip_model()->CloseAllTabs();
 }