Make UTF16ToASCII and UTF16TOUTF8 take a StringPiece

android_webview/renderer/aw_render_view_ext.cc

 // Copyright (c) 2012 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.
 
 #include "android_webview/renderer/aw_render_view_ext.h"
 
 #include <string>
 
 #include "android_webview/common/aw_hit_test_data.h"
 #include "android_webview/common/render_view_messages.h"
@@ skipping 62 matching lines @@
 bool RemovePrefixAndAssignIfMatches(const base::StringPiece& prefix,
                                     const GURL& url,
                                     std::string* dest) {
   const base::StringPiece spec(url.possibly_invalid_spec());
 
   if (spec.starts_with(prefix)) {
     url::RawCanonOutputW<1024> output;
     url::DecodeURLEscapeSequences(spec.data() + prefix.length(),
                                   spec.length() - prefix.length(),
                                   &output);
-    std::string decoded_url = base::UTF16ToUTF8(
-        base::string16(output.data(), output.length()));
-    dest->assign(decoded_url.begin(), decoded_url.end());
+    *dest = base::UTF16ToUTF8(
+        base::StringPiece16(output.data(), output.length()));
     return true;
   }
   return false;
 }
 
 void DistinguishAndAssignSrcLinkType(const GURL& url, AwHitTestData* data) {
   if (RemovePrefixAndAssignIfMatches(
       content::kAddressPrefix,
       url,
       &data->extra_data_for_type)) {
@@ skipping 219 matching lines @@
       page_scale_factor);
 }
 
 void AwRenderViewExt::OnSetBackgroundColor(SkColor c) {
   if (!render_view() || !render_view()->GetWebView())
     return;
   render_view()->GetWebView()->setBaseBackgroundColor(c);
 }
 
 }  // namespace android_webview