Have ViewsTestSuite initialize COM.

MaterialDesignController requires COM to be initialized.  Without this, various
views_unittests tests fail when run individually.  (This probably means there's
a second bug somewhere where something is holding COM initialized that shouldn't
be, or the tests would have failed all the time.)

It looks like initializing at the test suite level is roughly where other places
are doing this (e.g. ContentTestSuite), so hopefully this is the right place.

Bug: none
Change-Id: I5e6de4d45c6118b6a2bc69ba960904fa0fd8087d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1531422
Auto-Submit: Peter Kasting <pkasting@chromium.org>
Reviewed-by: Michael Wasserman <msw@chromium.org>
Commit-Queue: Peter Kasting <pkasting@chromium.org>
Cr-Commit-Position: refs/heads/master@{#642354}

ui/views/views_test_suite.h

@@ -7,13 +7,19 @@
 
 #include "base/test/test_suite.h"
 
-#if defined(USE_AURA)
-#include <memory>
+#include "build/build_config.h"
+
+#if defined(OS_WIN)
+#include "base/win/scoped_com_initializer.h"
 #endif
 
+#if defined(USE_AURA) && !defined(OS_CHROMEOS)
+#include <memory>
+
 namespace aura {
 class Env;
 }
+#endif
 
 namespace views {
 
@@ -42,6 +48,11 @@ class ViewsTestSuite : public base::TestSuite {
   // ViewsTestBase.
   std::unique_ptr<aura::Env> env_;
 #endif
+
+#if defined(OS_WIN)
+  base::win::ScopedCOMInitializer com_initializer_;
+#endif
+
   int argc_;
   char** argv_;