Fix error reporting position

Author: Yui T

src/compiler/binder.ts

@@ -89,7 +89,7 @@ module ts {
                     forEach(symbol.declarations, (declaration) => {
                         file.semanticErrors.push(createDiagnosticForNode(declaration.name, Diagnostics.Duplicate_identifier_0, getDisplayName(declaration)));
                     });
-                    file.semanticErrors.push(createDiagnosticForNode(node, Diagnostics.Duplicate_identifier_0, getDisplayName(node)));
+                    file.semanticErrors.push(createDiagnosticForNode(node.name, Diagnostics.Duplicate_identifier_0, getDisplayName(node)));
 
                     symbol = createSymbol(0, name);
                 }

src/compiler/checker.ts

@@ -5727,7 +5727,7 @@ module ts {
 
             if (duplicateFunctionDeclaration) {
                 forEach( declarations, declaration => {
-                    error(declaration, Diagnostics.Duplicate_function_implementation);
+                    error(declaration.name, Diagnostics.Duplicate_function_implementation);
                 });
             }