Skip base::string16 if not necessary for WebString <-> ASCII conversion

third_party/WebKit/Source/platform/exported/WebString.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 12 matching lines @@
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "public/platform/WebString.h"
 
+#include "base/strings/string_util.h"
+#include "wtf/text/ASCIIFastPath.h"
 #include "wtf/text/AtomicString.h"
 #include "wtf/text/CString.h"
 #include "wtf/text/StringUTF8Adaptor.h"
 #include "wtf/text/StringView.h"
 #include "wtf/text/WTFString.h"
 
 namespace blink {
 
 void WebString::reset() {
   m_private.reset();
@@ skipping 47 matching lines @@
                        string.length());
 
   CString latin1 = string.latin1();
   return std::string(latin1.data(), latin1.length());
 }
 
 WebString WebString::fromLatin1(const WebLChar* data, size_t length) {
   return String(data, length);
 }
 
+std::string WebString::ascii() const {
+  DCHECK(containsOnlyASCII());
+
+  if (isEmpty())
+    return std::string();
+
+  if (m_private->is8Bit()) {
+    return std::string(reinterpret_cast<const char*>(m_private->characters8()),
+                       m_private->length());
+  }
+
+  return std::string(m_private->characters16(),
+                     m_private->characters16() + m_private->length());
+}
+
+bool WebString::containsOnlyASCII() const {
+  return String(m_private.get()).containsOnlyASCII();
+}
+
+WebString WebString::fromASCII(const std::string& s) {
+  DCHECK(base::IsStringASCII(s));
+  return fromLatin1(s);
+}
+
 bool WebString::equals(const WebString& s) const {
   return equal(m_private.get(), s.m_private.get());
 }
 
 bool WebString::equals(const char* characters) const {
   return equal(m_private.get(), reinterpret_cast<const LChar*>(characters));
 }
 
 WebString::WebString(const WTF::String& s) : m_private(s.impl()) {}
 
@@ skipping 21 matching lines @@
 
 WebString::operator WTF::AtomicString() const {
   return WTF::AtomicString(m_private.get());
 }
 
 void WebString::assign(WTF::StringImpl* p) {
   m_private = p;
 }
 
 }  // namespace blink