Tidy up ScriptLoader (MIME) type matching.

third_party/WebKit/Source/platform/MIMETypeRegistry.h

Index: third_party/WebKit/Source/platform/MIMETypeRegistry.h
diff --git a/third_party/WebKit/Source/platform/MIMETypeRegistry.h b/third_party/WebKit/Source/platform/MIMETypeRegistry.h
index 2219007a5546e2c01528757167eaa6b8a1a2db08..95b9adc3ded4126c7dbdde616cd0255265a73cf3 100644
--- a/third_party/WebKit/Source/platform/MIMETypeRegistry.h
+++ b/third_party/WebKit/Source/platform/MIMETypeRegistry.h
@@ -34,6 +34,10 @@
 
 namespace blink {
 
+// Note/reminder: MIME type and parameter names are per-RFC case
+// insensitive (https://www.ietf.org/rfc/rfc2045.txt , section 5.1).
+// The MIMETypeRegistry predicates are all case-insensitive.
+
 // TODO(kinuko): Move this file under platform/network/mime.
 class PLATFORM_EXPORT MIMETypeRegistry {
   STATIC_ONLY(MIMETypeRegistry);