[JS BE] Make sourceMap generation more precise

- Don't produce mapping for closing bracket in case of expressionBody
 - Map Kt*Function declaration into corresponding js fun declaration
 - Update test data & add new test

js/js.parser/src/com/google/gwt/dev/js/rhino/Node.java

@@ -346,6 +346,10 @@ public class Node implements Cloneable {
         return position;
     }
 
+    public void setPosition(CodePosition position) {
+        this.position = position;
+    }
+
     /** Can only be called when <tt>getType() == TokenStream.NUMBER</tt> */
     public double getDouble() throws UnsupportedOperationException {
         throw new UnsupportedOperationException(this + " is not a number node");

js/js.parser/src/com/google/gwt/dev/js/rhino/Parser.java

@@ -222,7 +222,6 @@ public class Parser {
         int savedFunctionNumber = functionNumber;
         Node args;
         Node body;
-        CodePosition closingBracketPosition;
         try {
             functionNumber = 0;
             args = nf.createLeaf(TokenStream.LP, ts.tokenPosition);
@@ -241,7 +240,7 @@ public class Parser {
 
             mustMatchToken(ts, TokenStream.LC, "msg.no.brace.body");
             body = parseFunctionBody(ts);
-            closingBracketPosition = ts.tokenPosition;
+            body.setPosition(ts.tokenPosition);
             mustMatchToken(ts, TokenStream.RC, "msg.no.brace.after.body");
             // skip the last EOL so nested functions work...
         }
@@ -250,7 +249,7 @@ public class Parser {
             functionNumber = savedFunctionNumber;
         }
 
-        Node pn = nf.createFunction(nameNode, args, body, closingBracketPosition);
+        Node pn = nf.createFunction(nameNode, args, body, basePosition);
         if (memberExprNode != null) {
             pn = nf.createBinary(TokenStream.ASSIGN, TokenStream.NOP, memberExprNode, pn, basePosition);
         }