Reduce unnecessary usage of TextCaseSensitivity::TextCaseInsensitive.

third_party/WebKit/Source/core/dom/DOMImplementation.cpp

Index: third_party/WebKit/Source/core/dom/DOMImplementation.cpp
diff --git a/third_party/WebKit/Source/core/dom/DOMImplementation.cpp b/third_party/WebKit/Source/core/dom/DOMImplementation.cpp
index b6ef0586b9945e82e4c4a19b9dcd28dce67695e9..93c95f8082d067b704d164f35dfbbb978f3d6c6f 100644
--- a/third_party/WebKit/Source/core/dom/DOMImplementation.cpp
+++ b/third_party/WebKit/Source/core/dom/DOMImplementation.cpp
@@ -125,7 +125,7 @@ bool DOMImplementation::isXMLMIMEType(const String& mimeType) {
     return false;
 
   if (mimeType[0] == '/' || mimeType[length - 5] == '/' ||
-      !mimeType.endsWith("+xml", TextCaseInsensitive))
+      !mimeType.endsWith("+xml", TextCaseASCIIInsensitive))
     return false;
 
   bool hasSlash = false;
@@ -170,10 +170,10 @@ bool DOMImplementation::isXMLMIMEType(const String& mimeType) {
 }
 
 bool DOMImplementation::isJSONMIMEType(const String& mimeType) {
-  if (mimeType.startsWith("application/json", TextCaseInsensitive))
+  if (mimeType.startsWith("application/json", TextCaseASCIIInsensitive))
     return true;
-  if (mimeType.startsWith("application/", TextCaseInsensitive)) {
-    size_t subtype = mimeType.find("+json", 12, TextCaseInsensitive);
+  if (mimeType.startsWith("application/", TextCaseASCIIInsensitive)) {
+    size_t subtype = mimeType.find("+json", 12, TextCaseASCIIInsensitive);
     if (subtype != kNotFound) {
       // Just check that a parameter wasn't matched.
       size_t parameterMarker = mimeType.find(";");
@@ -189,7 +189,7 @@ bool DOMImplementation::isJSONMIMEType(const String& mimeType) {
 }
 
 static bool isTextPlainType(const String& mimeType) {
-  return mimeType.startsWith("text/", TextCaseInsensitive) &&
+  return mimeType.startsWith("text/", TextCaseASCIIInsensitive) &&
          !(equalIgnoringCase(mimeType, "text/html") ||
            equalIgnoringCase(mimeType, "text/xml") ||
            equalIgnoringCase(mimeType, "text/xsl"));