Update TabCapturePerformanceTest to more accurately time captures.

chrome/browser/extensions/api/tab_capture/tab_capture_performancetest.cc

Index: chrome/browser/extensions/api/tab_capture/tab_capture_performancetest.cc
diff --git a/chrome/browser/extensions/api/tab_capture/tab_capture_performancetest.cc b/chrome/browser/extensions/api/tab_capture/tab_capture_performancetest.cc
index a86e94ebfeb0c5a78e7a8692144ef4631259c6b5..a3b51ddc7410aee06749df0b2291b147810cc917 100644
--- a/chrome/browser/extensions/api/tab_capture/tab_capture_performancetest.cc
+++ b/chrome/browser/extensions/api/tab_capture/tab_capture_performancetest.cc
@@ -205,10 +205,18 @@ class TabCapturePerformanceTest
     // This prints out the average time between capture events.
     // As the capture frame rate is capped at 30fps, this score
     // cannot get any better than (lower) 33.33 ms.
+    // TODO(ericrk): Remove the "Capture" result once we are confident that
+    // "CaptureSucceeded" is giving the coverage we want. crbug.com/489817
     EXPECT_TRUE(PrintResults(analyzer.get(),
                              test_name,
                              "Capture",
                              "ms"));
+
+    // Also track the CaptureSucceeded event. Capture only indicates that a
+    // capture was requested, but this capture may later be aborted without
+    // running. CaptureSucceeded tracks successful frame captures.
+    EXPECT_TRUE(
+        PrintResults(analyzer.get(), test_name, "CaptureSucceeded", "ms"));
   }
 };