Sync the HTMLTableElement return types with the spec

third_party/WebKit/Source/core/html/HTMLTableElement.idl

Index: third_party/WebKit/Source/core/html/HTMLTableElement.idl
diff --git a/third_party/WebKit/Source/core/html/HTMLTableElement.idl b/third_party/WebKit/Source/core/html/HTMLTableElement.idl
index e1c3caae244d084f3e01719f5978288d773c9576..09e0a65f31aad49aec5a5612524fa5ab888bb7b5 100644
--- a/third_party/WebKit/Source/core/html/HTMLTableElement.idl
+++ b/third_party/WebKit/Source/core/html/HTMLTableElement.idl
@@ -23,18 +23,18 @@
 interface HTMLTableElement : HTMLElement {
     // TODO(philipj): The caption, tHead and tFoot setters should never throw.
     [RaisesException=Setter, LegacyInterfaceTypeChecking] attribute HTMLTableCaptionElement? caption;
-    HTMLElement createCaption();
+    HTMLTableCaptionElement createCaption();
     void deleteCaption();
     [RaisesException=Setter, LegacyInterfaceTypeChecking] attribute HTMLTableSectionElement? tHead;
-    HTMLElement createTHead();
+    HTMLTableSectionElement createTHead();
     void deleteTHead();
     [RaisesException=Setter, LegacyInterfaceTypeChecking] attribute HTMLTableSectionElement? tFoot;
-    HTMLElement createTFoot();
+    HTMLTableSectionElement createTFoot();
     void deleteTFoot();
     readonly attribute HTMLCollection tBodies;
-    HTMLElement createTBody();
+    HTMLTableSectionElement createTBody();
     readonly attribute HTMLCollection rows;
-    [RaisesException] HTMLElement insertRow(optional long index = -1);
+    [RaisesException] HTMLTableRowElement insertRow(optional long index = -1);
     [RaisesException] void deleteRow(long index);
     // attribute boolean sortable;
     // void stopSorting();