Remove unused test-only includes from content/shell/browser.

R=avi@chromium.org

Change-Id: I82773ba75a97887d57ccbbb21b54c45193da0729
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2121082Reviewed-by: Avi Drissman <avi@chromium.org>
Auto-Submit: danakj <danakj@chromium.org>
Commit-Queue: danakj <danakj@chromium.org>
Cr-Commit-Position: refs/heads/master@{#753430}

content/shell/browser/shell_content_browser_client.cc

@@ -40,8 +40,6 @@
 #include "content/shell/browser/shell_devtools_manager_delegate.h"
 #include "content/shell/browser/shell_quota_permission_context.h"
 #include "content/shell/browser/shell_web_contents_view_delegate_creator.h"
-#include "content/shell/common/blink_test.mojom.h"
-#include "content/shell/common/power_monitor_test.mojom.h"
 #include "content/shell/common/shell_switches.h"
 #include "content/shell/common/web_test/fake_bluetooth_chooser.mojom.h"
 #include "content/shell/common/web_test/web_test_bluetooth_fake_adapter_setter.mojom.h"