mojo-js: Fix SIMPLE_OPTIMIZATIONS for mojo_bindings_lite.js

Adds @provideGoog to compile_preamble.js to tell the compiler that the
file provides the goog namespace. Without this, compile_preamble.js is
compiled after bindings_lite.js and causes runtime errors when
"goog" methods get called by bindings_lite.js.

This issue only comes up when compiling with SIMPLE_OPTIMIZATIONS.
Compiling with ADVANCED_OPTIMIZATIONS worked correctly.

Change-Id: Ia26bdc31e13002c60503813a41ba9613cd764a88
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1847608Reviewed-by: Ken Rockot <rockot@google.com>
Commit-Queue: Giovanni Ortuño Urquidi <ortuno@chromium.org>
Cr-Commit-Position: refs/heads/master@{#704356}

mojo/public/js/compile_preamble.js

@@ -7,6 +7,8 @@
  * @fileoverview Preamble for JavaScript to be compiled with Closure Compiler.
  * We don't comple against the Closure library, so this provides a minimal set
  * of 'goog' namespace properties to support things like symbol exports.
+ *
+ * @provideGoog
  */
 
 /** @const */