2016-03-02T18:53:01 LayoutPosition

third_party/WebKit/Source/core/editing/DOMSelection.cpp

Index: third_party/WebKit/Source/core/editing/DOMSelection.cpp
diff --git a/third_party/WebKit/Source/core/editing/DOMSelection.cpp b/third_party/WebKit/Source/core/editing/DOMSelection.cpp
index 7155e70ea780ae1e990f77b41c6aea6e7900229c..3f79f98bd83fda03b008b4e513b810520e6dc976 100644
--- a/third_party/WebKit/Source/core/editing/DOMSelection.cpp
+++ b/third_party/WebKit/Source/core/editing/DOMSelection.cpp
@@ -288,6 +288,14 @@ void DOMSelection::setBaseAndExtent(Node* baseNode, int baseOffset, Node* extent
     if (!isValidForPosition(baseNode) || !isValidForPosition(extentNode))
         return;
 
+    // We check |DocumentTypeNode| here instead of |isValidForPosition()|,
+    // since, |collapse()| throws error for |DocumentTypeNode|, but
+    // |setBaseAndExtent()| doesn't.
+    if (baseNode && baseNode->isDocumentTypeNode())
+        return;
+    if (extentNode && extentNode->isDocumentTypeNode())
+        return;
+
     VisiblePosition visibleBase = createVisiblePosition(createPosition(baseNode, baseOffset));
     VisiblePosition visibleExtent = createVisiblePosition(createPosition(extentNode, extentOffset));
 
@@ -363,6 +371,12 @@ void DOMSelection::extend(Node* node, int offset, ExceptionState& exceptionState
     if (!isValidForPosition(node))
         return;
 
+    // We check |DocumentTypeNode| here instead of |isValidForPosition()|,
+    // since, |collapse()| throws error for |DocumentTypeNode|, but
+    // |setBaseAndExtent()| doesn't.
+    if (node && node->isDocumentTypeNode())
+        return;
+
     m_frame->selection().setExtent(createVisiblePosition(createPosition(node, offset)));
 }