Expand WTF::StringView's API to be more like StringPiece.

third_party/WebKit/Source/wtf/text/WTFString.h

Index: third_party/WebKit/Source/wtf/text/WTFString.h
diff --git a/third_party/WebKit/Source/wtf/text/WTFString.h b/third_party/WebKit/Source/wtf/text/WTFString.h
index 8d01437df9b2314a390c9d56513ad6af83386194..4b809023cf568ab24898a5bd38a0b0ebb586e7ce 100644
--- a/third_party/WebKit/Source/wtf/text/WTFString.h
+++ b/third_party/WebKit/Source/wtf/text/WTFString.h
@@ -343,9 +343,6 @@ public:
     String left(unsigned len) const { return substring(0, len); }
     String right(unsigned len) const { return substring(length() - len, len); }
 
-    StringView createView() const { return StringView(impl()); }
-    StringView createView(unsigned offset, unsigned length) const { return StringView(impl(), offset, length); }
-
     // Returns a lowercase/uppercase version of the string
     String lower() const;
     String upper() const;
@@ -667,6 +664,13 @@ inline void String::prependTo(Vector<UChar, inlineCapacity>& result, unsigned po
     }
 }
 
+inline StringView::StringView(const String& string)
+    : StringView(string, 0, string.length()) {}
+inline StringView::StringView(const String& string, unsigned offset, unsigned length)
+    : StringView(string.impl(), offset, length) {}
+inline StringView::StringView(const String& string, unsigned offset)
+    : StringView(string.impl(), offset) {}
+
 // StringHash is the default hash for String
 template<typename T> struct DefaultHash;
 template<> struct DefaultHash<String> {