Update comments on some tests to clarify their associated bugs.

Bug: 396347, 445155, 911949
TBR: kylixrd
Change-Id: I72d14d9cc3a80be89c039c654204fd0b38fb6dbc
Reviewed-on: https://chromium-review.googlesource.com/c/1413659Reviewed-by: Peter Kasting <pkasting@chromium.org>
Commit-Queue: Peter Kasting <pkasting@chromium.org>
Cr-Commit-Position: refs/heads/master@{#622962}

chrome/browser/ui/browser_browsertest.cc

@@ -611,7 +611,6 @@ IN_PROC_BROWSER_TEST_F(BrowserTest, ClearPendingOnFailUnlessNTP) {
 
 // Test for crbug.com/297289.  Ensure that modal dialogs are closed when a
 // cross-process navigation is ready to commit.
-// Flaky test, see https://crbug.com/445155.
 IN_PROC_BROWSER_TEST_F(BrowserTest, CrossProcessNavCancelsDialogs) {
   ASSERT_TRUE(embedded_test_server()->Start());
   GURL url(embedded_test_server()->GetURL("/empty.html"));
@@ -2316,7 +2315,6 @@ IN_PROC_BROWSER_TEST_F(ClickModifierTest, HrefControlClickTest) {
 
 // Control-shift-clicks open in a foreground tab.
 // On OSX meta [the command key] takes the place of control.
-// http://crbug.com/396347
 IN_PROC_BROWSER_TEST_F(ClickModifierTest, HrefControlShiftClickTest) {
 #if defined(OS_MACOSX)
   int modifiers = blink::WebInputEvent::kMetaKey;
@@ -2338,7 +2336,6 @@ IN_PROC_BROWSER_TEST_F(ClickModifierTest, HrefMiddleClickTest) {
 }
 
 // Shift-middle-clicks open in a foreground tab.
-// http://crbug.com/396347
 IN_PROC_BROWSER_TEST_F(ClickModifierTest, HrefShiftMiddleClickTest) {
   int modifiers = blink::WebInputEvent::kShiftKey;
   blink::WebMouseEvent::Button button = blink::WebMouseEvent::Button::kMiddle;

chrome/browser/ui/views/frame/top_controls_slide_controller_chromeos_browsertest.cc

@@ -575,6 +575,7 @@ IN_PROC_BROWSER_TEST_F(TopControlsSlideControllerTest, TestScrollingPage) {
                                TopChromeShownState::kFullyShown);
 }
 
+// TODO(https://crbug.com/911949): Times out on CrOS on the waterfall.
 IN_PROC_BROWSER_TEST_F(TopControlsSlideControllerTest,
                        DISABLED_TestScrollingPageAndSwitchingToNTP) {
   ToggleTabletMode();