Add test for accessibility histograms.

The goal is just to make sure this code has test coverage, not to test
correctness. There was an issue in the past where the code that computed
the histograms crashed in debug mode, this will help prevent something like
that from landing in the future.

BUG=99504


Review URL: https://chromiumcodereview.appspot.com/11778045

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@175677 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 15 insertions, 7 deletions

diff --git a/content/browser/accessibility/browser_accessibility_state_impl.cc b/content/browser/accessibility/browser_accessibility_state_impl.cc
index 2f6e0c3..3cb73fe 100644
--- a/content/browser/accessibility/browser_accessibility_state_impl.cc
+++ b/content/browser/accessibility/browser_accessibility_state_impl.cc
@@ -50,12 +50,12 @@ BrowserAccessibilityStateImpl::BrowserAccessibilityStateImpl()
   }
 
 #if defined(OS_WIN)
-  // On Windows, UpdateHistogram calls some system functions with unknown
+  // On Windows, UpdateHistograms calls some system functions with unknown
   // runtime, so call it on the file thread to ensure there's no jank.
   // Everything in that method must be safe to call on another thread.
   BrowserThread::ID update_histogram_thread = BrowserThread::FILE;
 #else
-  // On all other platforms, UpdateHistogram should be called on the main
+  // On all other platforms, UpdateHistograms should be called on the main
   // thread.
   BrowserThread::ID update_histogram_thread = BrowserThread::UI;
 #endif
@@ -65,7 +65,7 @@ BrowserAccessibilityStateImpl::BrowserAccessibilityStateImpl()
   AddRef();
   BrowserThread::PostDelayedTask(
       update_histogram_thread, FROM_HERE,
-      base::Bind(&BrowserAccessibilityStateImpl::UpdateHistogram, this),
+      base::Bind(&BrowserAccessibilityStateImpl::UpdateHistograms, this),
       base::TimeDelta::FromSeconds(kAccessibilityHistogramDelaySecs));
 }
 
@@ -94,7 +94,11 @@ void BrowserAccessibilityStateImpl::AddHistogramCallback(
   histogram_callbacks_.push_back(callback);
 }
 
-void BrowserAccessibilityStateImpl::UpdateHistogram() {
+void BrowserAccessibilityStateImpl::UpdateHistogramsForTesting() {
+  UpdateHistograms();
+}
+
+void BrowserAccessibilityStateImpl::UpdateHistograms() {
   UpdatePlatformSpecificHistograms();
 
   for (size_t i = 0; i < histogram_callbacks_.size(); ++i)
diff --git a/content/browser/accessibility/browser_accessibility_state_impl.h b/content/browser/accessibility/browser_accessibility_state_impl.h
index 40d99fd..46621ea 100644
--- a/content/browser/accessibility/browser_accessibility_state_impl.h
+++ b/content/browser/accessibility/browser_accessibility_state_impl.h
@@ -45,9 +45,7 @@ class CONTENT_EXPORT BrowserAccessibilityStateImpl
   virtual bool IsAccessibleBrowser() OVERRIDE;
   virtual void AddHistogramCallback(base::Closure callback) OVERRIDE;
 
-  // Called a short while after startup to allow time for the accessibility
-  // state to be determined. Updates a histogram with the current state.
-  void UpdateHistogram();
+  virtual void UpdateHistogramsForTesting() OVERRIDE;
 
   AccessibilityMode GetAccessibilityMode();
   void SetAccessibilityMode(AccessibilityMode mode);
@@ -56,6 +54,10 @@ class CONTENT_EXPORT BrowserAccessibilityStateImpl
   friend class base::RefCountedThreadSafe<BrowserAccessibilityStateImpl>;
   friend struct DefaultSingletonTraits<BrowserAccessibilityStateImpl>;
 
+  // Called a short while after startup to allow time for the accessibility
+  // state to be determined. Updates histograms with the current state.
+  void UpdateHistograms();
+
   // Leaky singleton, destructor generally won't be called.
   virtual ~BrowserAccessibilityStateImpl();
 
diff --git a/content/public/browser/browser_accessibility_state.h b/content/public/browser/browser_accessibility_state.h
index 4c89f5a..16cf706 100644
--- a/content/public/browser/browser_accessibility_state.h
+++ b/content/public/browser/browser_accessibility_state.h
@@ -34,6 +34,8 @@ class CONTENT_EXPORT BrowserAccessibilityState {
   // Use this to register a method to update additional accessibility
   // histograms.
   virtual void AddHistogramCallback(base::Closure callback) = 0;
+
+  virtual void UpdateHistogramsForTesting() = 0;
 };
 
 }  // namespace content