Make EarlGrey matchers compliant with Chromium style.

ios/testing/earl_grey/matchers.h

 // Copyright 2016 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.
 
 #ifndef IOS_TESTING_EARL_GREY_MATCHERS_H_
 #define IOS_TESTING_EARL_GREY_MATCHERS_H_
 
 #import <Foundation/Foundation.h>
 
 #import <EarlGrey/EarlGrey.h>
 
 namespace testing {
 
 // Matcher for context menu item whose text is exactly |text|.
-id<GREYMatcher> contextMenuItemWithText(NSString* text);
+id<GREYMatcher> ContextMenuItemWithText(NSString* text);
 
 // Matcher for a UI element to tap to dismiss the the context menu, where
 // |cancel_text| is the localized text used for the action sheet cancel control.
 // On phones, where the context menu is an action sheet, this will be a matcher
 // for the menu item with |cancel_text| as its label.
 // On tablets, where the context menu is a popover, this will be a matcher for
 // some element outside of the popover.
-id<GREYMatcher> elementToDismissContextMenu(NSString* cancel_text);
+id<GREYMatcher> ElementToDismissContextMenu(NSString* cancel_text);
 
 }  // namespace testing
 
 #endif  // IOS_TESTING_EARL_GREY_MATCHERS_H_