Change string16 to std::string in the gfx::Font() interface.

chrome/browser/ui/cocoa/omnibox/omnibox_popup_view_mac_unittest.mm

 // Copyright (c) 2011 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 "chrome/browser/ui/cocoa/omnibox/omnibox_popup_view_mac.h"
 
 #include "base/memory/scoped_ptr.h"
 #include "base/sys_string_conversions.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/autocomplete/autocomplete.h"
 #include "testing/platform_test.h"
 #include "ui/base/text/text_elider.h"
 
 namespace {
 
 const float kLargeWidth = 10000;
 
 class OmniboxPopupViewMacTest : public PlatformTest {
  public:
   OmniboxPopupViewMacTest() {}
 
   virtual void SetUp() {
     PlatformTest::SetUp();
 
     // These are here because there is no autorelease pool for the
     // constructor.
     color_ = [NSColor blackColor];
     dimColor_ = [NSColor darkGrayColor];
     font_ = gfx::Font(
-        base::SysNSStringToUTF16([[NSFont userFontOfSize:12] fontName]), 12);
+        base::SysNSStringToUTF8([[NSFont userFontOfSize:12] fontName]), 12);
   }
 
   // Returns the length of the run starting at |location| for which
   // |attributeName| remains the same.
   static NSUInteger RunLengthForAttribute(NSAttributedString* string,
                                           NSUInteger location,
                                           NSString* attributeName) {
     const NSRange fullRange = NSMakeRange(0, [string length]);
     NSRange range;
     [string attribute:attributeName
@@ skipping 502 matching lines @@
 // updates the model's selection from the matrix before returning.
 // Could possibly test that via -select:.
 
 // TODO(shess): Test that AutocompleteButtonCell returns the right
 // background colors for on, highlighted, and neither.
 
 // TODO(shess): Test that AutocompleteMatrixTarget can be initialized
 // and then sends -select: to the view.
 
 }  // namespace