Implement the 'noopener' link relation.

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

Index: third_party/WebKit/Source/core/html/HTMLAnchorElement.h
diff --git a/third_party/WebKit/Source/core/html/HTMLAnchorElement.h b/third_party/WebKit/Source/core/html/HTMLAnchorElement.h
index 17161225c936aa4128728b58dca51fd4aa26b120..9eb662eb965eedb1ce8dbbeaab3b2d17012d5231 100644
--- a/third_party/WebKit/Source/core/html/HTMLAnchorElement.h
+++ b/third_party/WebKit/Source/core/html/HTMLAnchorElement.h
@@ -36,24 +36,25 @@ namespace blink {
 // Link relation bitmask values.
 // FIXME: Uncomment as the various link relations are implemented.
 enum {
-//     RelationAlternate   = 0x00000001,
-//     RelationArchives    = 0x00000002,
-//     RelationAuthor      = 0x00000004,
-//     RelationBoomark     = 0x00000008,
-//     RelationExternal    = 0x00000010,
-//     RelationFirst       = 0x00000020,
-//     RelationHelp        = 0x00000040,
-//     RelationIndex       = 0x00000080,
-//     RelationLast        = 0x00000100,
-//     RelationLicense     = 0x00000200,
-//     RelationNext        = 0x00000400,
-//     RelationNoFolow    = 0x00000800,
-    RelationNoReferrer     = 0x00001000,
-//     RelationPrev        = 0x00002000,
-//     RelationSearch      = 0x00004000,
-//     RelationSidebar     = 0x00008000,
-//     RelationTag         = 0x00010000,
-//     RelationUp          = 0x00020000,
+    //     RelationAlternate   = 0x00000001,
+    //     RelationArchives    = 0x00000002,
+    //     RelationAuthor      = 0x00000004,
+    //     RelationBoomark     = 0x00000008,
+    //     RelationExternal    = 0x00000010,
+    //     RelationFirst       = 0x00000020,
+    //     RelationHelp        = 0x00000040,
+    //     RelationIndex       = 0x00000080,
+    //     RelationLast        = 0x00000100,
+    //     RelationLicense     = 0x00000200,
+    //     RelationNext        = 0x00000400,
+    //     RelationNoFolow    = 0x00000800,
+    RelationNoReferrer = 0x00001000,
+    //     RelationPrev        = 0x00002000,
+    //     RelationSearch      = 0x00004000,
+    //     RelationSidebar     = 0x00008000,
+    //     RelationTag         = 0x00010000,
+    //     RelationUp          = 0x00020000,
+    RelationNoOpener = 0x00040000,

[Mike West, 2015/11/15 08:17:39]

`git cl format`.

 };
 
 class CORE_EXPORT HTMLAnchorElement : public HTMLElement, public DOMURLUtils {