[headless] Fix screenshots with gpu enabled.

headless/test/headless_browser_test.h

Index: headless/test/headless_browser_test.h
diff --git a/headless/test/headless_browser_test.h b/headless/test/headless_browser_test.h
index 3db973b02e5490ca3c4a7107a56b9a2a168ee461..1a258ceccb33d93bad481fa22f0b9451e8aa4fe9 100644
--- a/headless/test/headless_browser_test.h
+++ b/headless/test/headless_browser_test.h
@@ -94,6 +94,10 @@ class HeadlessBrowserTest : public content::BrowserTestBase {
   IN_PROC_BROWSER_TEST_F(TEST_FIXTURE_NAME, RunAsyncTest) { RunTest(); } \
   class AsyncHeadlessBrowserTestNeedsSemicolon##TEST_FIXTURE_NAME {}
 
+#define HEADLESS_ASYNC_DEVTOOLED_TEST_P(TEST_FIXTURE_NAME)               \
+  IN_PROC_BROWSER_TEST_P(TEST_FIXTURE_NAME, RunAsyncTest) { RunTest(); } \
+  class AsyncHeadlessBrowserTestNeedsSemicolon##TEST_FIXTURE_NAME {}
+
 // Base class for tests that require access to a DevToolsClient. Subclasses
 // should override the RunDevTooledTest() method, which is called asynchronously
 // when the DevToolsClient is ready.