Use StringView for equalIgnoringCase.

third_party/WebKit/Source/wtf/text/StringView.cpp

 // 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.
 
 #include "wtf/text/StringView.h"
 
 #include "wtf/text/AtomicString.h"
 #include "wtf/text/WTFString.h"
 
 namespace WTF {
@@ skipping 45 matching lines @@
     if (a.is8Bit()) {
         if (b.is8Bit())
             return equal(a.characters8(), b.characters8(), a.length());
         return equal(a.characters8(), b.characters16(), a.length());
     }
     if (b.is8Bit())
         return equal(a.characters16(), b.characters8(), a.length());
     return equal(a.characters16(), b.characters16(), a.length());
 }
 
+
+bool equalIgnoringCaseAndNullity(const StringView& a, const StringView& b)
+{

[haraken, 2016/08/04 09:05:28]

Can we add:

  DCHECK(!a.isNull());
  DCHECK(!b.isNull());

?

[esprehn, 2016/08/04 18:30:07]

No since the semantics are that you still allow null strings, you just ignore
it. So you treat null strings as having a zero length instead of being special.

+    if (a.length() != b.length())
+        return false;
+    if (a.is8Bit()) {
+        if (b.is8Bit())
+            return equalIgnoringCase(a.characters8(), b.characters8(), a.length());
+        return equalIgnoringCase(a.characters8(), b.characters16(), a.length());
+    }
+    if (b.is8Bit())
+        return equalIgnoringCase(a.characters16(), b.characters8(), a.length());
+    return equalIgnoringCase(a.characters16(), b.characters16(), a.length());
+}
+
+bool equalIgnoringCase(const StringView& a, const StringView& b)
+{
+    if (a.isNull() || b.isNull())
+        return a.isNull() == b.isNull();
+    return equalIgnoringCaseAndNullity(a, b);
+}
+
 bool equalIgnoringASCIICase(const StringView& a, const StringView& b)
 {
     if (a.isNull() || b.isNull())
         return a.isNull() == b.isNull();
     if (a.length() != b.length())
         return false;
     if (a.is8Bit()) {
         if (b.is8Bit())
             return equalIgnoringASCIICase(a.characters8(), b.characters8(), a.length());
         return equalIgnoringASCIICase(a.characters8(), b.characters16(), a.length());
     }
     if (b.is8Bit())
         return equalIgnoringASCIICase(a.characters16(), b.characters8(), a.length());
     return equalIgnoringASCIICase(a.characters16(), b.characters16(), a.length());
 }
 
 } // namespace WTF