Fix parser errors (#395)

Author: chipshort

src/checkstyle/token/walk/WalkFunction.hx

@@ -34,6 +34,7 @@ class WalkFunction {
 		parent.addChild(pOpen);
 		var progress:TokenStreamProgress = new TokenStreamProgress(stream);
 		while (progress.streamHasChanged()) {
+			WalkComment.walkComment(stream, pOpen);
 			if (stream.is(PClose)) break;
 			WalkFieldDef.walkFieldDef(stream, pOpen);
 		}

src/checkstyle/token/walk/WalkStatement.hx

@@ -156,7 +156,7 @@ class WalkStatement {
 
 	static function findQuestionParent(token:TokenTree):TokenTree {
 		var parent:TokenTree = token;
-		while (parent.tok != null) {
+		while (parent != null && parent.tok != null) {
 			switch (parent.tok) {
 				case Question: return parent;
 				case Comma: return null;

test/token/TokenTreeBuilderParsingTest.hx

@@ -30,6 +30,7 @@ class TokenTreeBuilderParsingTest {
 		assertCodeParses(OBJECT_WITH_ARRAY);
 		assertCodeParses(MACRO_REIFICATION);
 		assertCodeParses(BLOCK_METADATA);
+		assertCodeParses(COMMENTS_IN_FUNCTION_PARAMS);
 	}
 
 	public function assertCodeParses(code:String, ?pos:PosInfos) {
@@ -393,4 +394,11 @@ abstract TokenTreeBuilderParsingTests(String) to String {
 		}
 	}";
 
+	var COMMENTS_IN_FUNCTION_PARAMS = "
+	class Test {
+		function test( /* comment */ a:String /* comment */) { }
+		function test2( /* comment */ /* comment */) { }
+	}
+	";
+
 }