Add 5 experimental accessibility features on Chrome OS.

chrome/common/pref_names.h

Index: chrome/common/pref_names.h
diff --git a/chrome/common/pref_names.h b/chrome/common/pref_names.h
index 21b75d50c97fb2d66b36b98d6964f5c77af17cd3..25a2bb0dbd429257f9d6e9e3c1494ca4463f52c9 100644
--- a/chrome/common/pref_names.h
+++ b/chrome/common/pref_names.h
@@ -215,6 +215,11 @@ extern const char kAccessibilityScreenMagnifierScale[];
 extern const char kAccessibilityVirtualKeyboardEnabled[];
 extern const char kAccessibilityAutoclickEnabled[];
 extern const char kAccessibilityAutoclickDelayMs[];
+extern const char kAccessibilityCaretHighlightEnabled[];
+extern const char kAccessibilityCursorHighlightEnabled[];
+extern const char kAccessibilityFocusHighlightEnabled[];
+extern const char kAccessibilitySelectToSpeakEnabled[];
+extern const char kAccessibilitySwitchAccessEnabled[];
 extern const char kShouldAlwaysShowAccessibilityMenu[];
 extern const char kLabsAdvancedFilesystemEnabled[];
 extern const char kLabsMediaplayerEnabled[];