Parse comments without recursion to avoid RangeError.

Fixes #993

test/mocha/huge-number-of-comments.js

@@ -0,0 +1,19 @@
+var Uglify = require('../../');
+var assert = require("assert");
+
+describe("Huge number of comments.", function() {
+    it("Should parse and compress code with thousands of consecutive comments", function() {
+        var js = 'function lots_of_comments(x) { return 7 -';
+        var i;
+        for (i = 1; i <= 5000; ++i) { js += "// " + i + "\n"; }
+        for (; i <= 10000; ++i) { js += "/* " + i + " */ /**/"; }
+        js += "x; }";
+        var result = Uglify.minify(js, {
+            fromString: true,
+            mangle: false,
+            compress: {}
+        });
+        assert.strictEqual(result.code, "function lots_of_comments(x){return 7-x}");
+    });
+});
+