Reland "Enable device/vr unittests on non-Android platforms"

This reverts commit 1e0c32df.

Reason for revert: Fix issue that caused revert.

Tested unit tests on Windows with component and non-component build.

Original change's description:
> Revert "Enable device/vr unittests on non-Android platforms"
>
> This reverts commit 11ee8e61.
>
> Reason for revert: Suspected causing build failure on WebKit Win Builder (dbg)
> https://ci.chromium.org/buildbot/chromium.webkit/WebKit%20Win%20Builder%20%28dbg%29/131035
>
> Original change's description:
> > Enable device/vr unittests on non-Android platforms
> >
> > Change-Id: I76eed7cf354d7f55e5409035941b76100d772b96
> > Reviewed-on: https://chromium-review.googlesource.com/1053093
> > Reviewed-by: Michael Thiessen <mthiesse@chromium.org>
> > Commit-Queue: Bill Orr <billorr@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#557320}
>
> TBR=mthiesse@chromium.org,billorr@chromium.org
>
> Change-Id: Ice684f6a36892c3b73c789617d40718a40d01745
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Reviewed-on: https://chromium-review.googlesource.com/1053153
> Reviewed-by: Thomas Anderson <thomasanderson@chromium.org>
> Commit-Queue: Thomas Anderson <thomasanderson@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#557346}

TBR=mthiesse@chromium.org,thomasanderson@chromium.org,billorr@chromium.org

Change-Id: Icbeef0d1e1c9649cdebe9bdfa9a670399c7aa0c9
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/1053248
Commit-Queue: Bill Orr <billorr@chromium.org>
Reviewed-by: Bill Orr <billorr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#557579}

device/BUILD.gn

@@ -283,7 +283,7 @@ test("device_unittests") {
     ]
   }
 
-  if (enable_vr && is_android) {
+  if (enable_vr) {
     sources += [
       "vr/orientation/orientation_device_provider_unittest.cc",
       "vr/orientation/orientation_device_unittest.cc",
@@ -291,10 +291,15 @@ test("device_unittests") {
       "vr/vr_display_impl_unittest.cc",
     ]
 
+    if (is_android) {
+      deps += [ "//device/vr:java" ]
+    }
+
+    defines = [ "DEVICE_VR_IMPLEMENTATION" ]
+
     deps += [
       "//device/vr",
       "//device/vr:fakes",
-      "//device/vr:java",
       "//device/vr/public/mojom",
       "//services/device/public/cpp/generic_sensor",
       "//ui/display",