Selection API: Some functions should throw InvalidNodeTypeError and IndexSizeError.

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 51727bb61623b756fa56932170375529f905591e..20b6dfd4de3acc5c7105b96853e749e006df6086 100644
--- a/third_party/WebKit/Source/core/editing/DOMSelection.cpp
+++ b/third_party/WebKit/Source/core/editing/DOMSelection.cpp
@@ -197,13 +197,13 @@ void DOMSelection::collapse(Node* node,
         IndexSizeError, String::number(offset) + " is not a valid offset.");
     return;
   }
-
-  if (!isValidForPosition(node))
-    return;
   Range::checkNodeWOffset(node, offset, exceptionState);
   if (exceptionState.hadException())
     return;
 
+  if (!isValidForPosition(node))
+    return;
+
   frame()->selection().setSelection(
       SelectionInDOMTree::Builder()
           .collapse(Position(node, offset))
@@ -285,6 +285,15 @@ void DOMSelection::setBaseAndExtent(Node* baseNode,
     extentOffset = 0;
   }
 
+  Range::checkNodeWOffset(baseNode, baseOffset, exceptionState);
+  if (exceptionState.hadException())
+    return;
+  if (extentNode) {
+    Range::checkNodeWOffset(extentNode, extentOffset, exceptionState);
+    if (exceptionState.hadException())
+      return;
+  }
+
   if (!isValidForPosition(baseNode) || !isValidForPosition(extentNode))
     return;
 
@@ -380,12 +389,9 @@ void DOMSelection::extend(Node* node,
         IndexSizeError, String::number(offset) + " is not a valid offset.");
     return;
   }
-  if (static_cast<unsigned>(offset) > node->lengthOfContents()) {
-    exceptionState.throwDOMException(
-        IndexSizeError,
-        String::number(offset) + " is larger than the given node's length.");
+  Range::checkNodeWOffset(node, offset, exceptionState);
+  if (exceptionState.hadException())
     return;
-  }
 
   if (!isValidForPosition(node))
     return;