Implement support for link type serviceworker in link elements.

third_party/WebKit/Source/core/html/LinkRelAttribute.h

Index: third_party/WebKit/Source/core/html/LinkRelAttribute.h
diff --git a/third_party/WebKit/Source/core/html/LinkRelAttribute.h b/third_party/WebKit/Source/core/html/LinkRelAttribute.h
index 5230d3af22f65064a10c676354cbd203c473c409..11e7bf961faaa129116c4ae682399b1875f62b0a 100644
--- a/third_party/WebKit/Source/core/html/LinkRelAttribute.h
+++ b/third_party/WebKit/Source/core/html/LinkRelAttribute.h
@@ -55,6 +55,7 @@ public:
     bool isLinkNext() const { return m_isLinkNext; }
     bool isImport() const { return m_isImport; }
     bool isManifest() const { return m_isManifest; }
+    bool isServiceWorker() const { return m_isServiceWorker; }
 
 private:
     IconType m_iconType;
@@ -68,6 +69,7 @@ private:
     bool m_isLinkNext : 1;
     bool m_isImport : 1;
     bool m_isManifest : 1;
+    bool m_isServiceWorker : 1;
 };
 
 } // namespace blink