Make custom GREYAction methods Chromium C-Style.

ios/chrome/browser/context_menu/context_menu_egtest.mm

 // 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.
 
 #import <EarlGrey/EarlGrey.h>
 #import <UIKit/UIKit.h>
 #import <XCTest/XCTest.h>
 
 #include "base/strings/sys_string_conversions.h"
 #include "ios/chrome/browser/ui/ui_util.h"
@@ skipping 61 matching lines @@
              @"Waiting for matcher %@ failed.", contextMenuItemButton);
 }
 
 // Long press on |elementId| to trigger context menu and then tap on
 // |contextMenuItemButton| item.
 void LongPressElementAndTapOnButton(const char* elementId,
                                     id<GREYMatcher> contextMenuItemButton) {
   id<GREYMatcher> webViewMatcher =
       web::WebViewInWebState(chrome_test_util::GetCurrentWebState());
   [[EarlGrey selectElementWithMatcher:webViewMatcher]
-      performAction:chrome_test_util::longPressElementForContextMenu(elementId,
-                                                                     true)];
+      performAction:chrome_test_util::LongPressElementForContextMenu(
+                        elementId, true /* menu should appear */)];

[Eugene But (OOO till 7-30), 2017/03/24 16:24:31]

Do you want to fix valriable name? s/elementId/element_id

[baxley, 2017/03/24 16:48:07]

Done.

 
   [[EarlGrey selectElementWithMatcher:contextMenuItemButton]
       assertWithMatcher:grey_notNil()];
   [[EarlGrey selectElementWithMatcher:contextMenuItemButton]
       performAction:grey_tap()];
   WaitForContextMenuItemDisappeared(contextMenuItemButton);
 }
 
 // A simple wrapper that sleeps for 1s to wait for the animation, triggered from
 // opening a new tab through context menu, to finish before selecting tab.
@@ skipping 162 matching lines @@
   SelectTabAtIndexInCurrentMode(1U);
 
   // Verify url and tab count.
   [[EarlGrey selectElementWithMatcher:chrome_test_util::OmniboxText(
                                           destinationURL.GetContent())]
       assertWithMatcher:grey_notNil()];
   chrome_test_util::AssertMainTabCount(2U);
 }
 
 @end