fix parsing of property access after new line (#1944)

Account for comments when detecting property access in `tokenizer`.

fixes #1943

test/compress/issue-1943.js

@@ -0,0 +1,31 @@
+operator: {
+    input: {
+        a. //comment
+        typeof
+    }
+    expect_exact: "a.typeof;"
+}
+
+name: {
+    input: {
+        a. //comment
+        b
+    }
+    expect_exact: "a.b;"
+}
+
+keyword: {
+    input: {
+        a. //comment
+        default
+    }
+    expect_exact: "a.default;"
+}
+
+atom: {
+    input: {
+        a. //comment
+        true
+    }
+    expect_exact: "a.true;"
+}