Add UMA histogram for sticky keys.

BUG=335757

Review URL: https://codereview.chromium.org/131513014

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@250794 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/browser/chromeos/accessibility/accessibility_manager.cc b/chrome/browser/chromeos/accessibility/accessibility_manager.cc
index 37f44683..9274012 100644
--- a/chrome/browser/chromeos/accessibility/accessibility_manager.cc
+++ b/chrome/browser/chromeos/accessibility/accessibility_manager.cc
@@ -850,6 +850,7 @@
                         IsHighContrastEnabled());
   UMA_HISTOGRAM_BOOLEAN("Accessibility.CrosVirtualKeyboard",
                         IsVirtualKeyboardEnabled());
+  UMA_HISTOGRAM_BOOLEAN("Accessibility.CrosStickyKeys", IsStickyKeysEnabled());
   if (MagnificationManager::Get()) {
     uint32 type = MagnificationManager::Get()->IsMagnifierEnabled() ?
                       MagnificationManager::Get()->GetMagnifierType() : 0;