Don't handle the tab press event in the window cycle event filter.

ash/wm/window_cycle_controller_unittest.cc

Index: ash/wm/window_cycle_controller_unittest.cc
diff --git a/ash/wm/window_cycle_controller_unittest.cc b/ash/wm/window_cycle_controller_unittest.cc
index ad61331fc9d2040e3e076c45d4054fcd25f5f6c4..142bc389aa2745e086e7a007e04dd28e6fb24fa0 100644
--- a/ash/wm/window_cycle_controller_unittest.cc
+++ b/ash/wm/window_cycle_controller_unittest.cc
@@ -14,6 +14,7 @@
 #include "ash/common/shell_window_ids.h"
 #include "ash/common/wm/window_cycle_list.h"
 #include "ash/common/wm/window_state.h"
+#include "ash/common/wm/wm_event.h"
 #include "ash/common/wm_shell.h"
 #include "ash/shelf/shelf.h"
 #include "ash/shelf/shelf_widget.h"
@@ -615,4 +616,34 @@ TEST_F(WindowCycleControllerTest, TabKeyNotLeaked) {
   EXPECT_EQ(0u, key_count.GetCountAndReset());
 }
 
+// Tests that we can cycle past fullscreen windows: https://crbug.com/622396.
+// Fullscreen windows are special in that they are allowed to handle alt+tab
+// keypresses, which means the window cycle event filter should not handle
+// the tab press else it prevents cycling past that window.
+TEST_F(WindowCycleControllerTest, TabPastFullscreenWindow) {
+  std::unique_ptr<Window> w0(CreateTestWindowInShellWithId(0));
+  std::unique_ptr<Window> w1(CreateTestWindowInShellWithId(1));
+  wm::WMEvent maximize_event(wm::WM_EVENT_FULLSCREEN);
+  wm::GetWindowState(w1.get())->Activate();
+  wm::GetWindowState(w1.get())->OnWMEvent(&maximize_event);
+  EXPECT_TRUE(wm::GetWindowState(w1.get())->IsFullscreen());
+  wm::GetWindowState(w0.get())->Activate();
+
+  ui::test::EventGenerator& generator = GetEventGenerator();

[varkha, 2016/08/17 18:06:57]

nit: Could swap the line before and above this comment.

[flackr, 2016/08/17 19:07:19]

Done.

+  EXPECT_TRUE(wm::GetWindowState(w0.get())->IsActive());
+  generator.PressKey(ui::VKEY_MENU, ui::EF_NONE);
+
+  generator.PressKey(ui::VKEY_TAB, ui::EF_ALT_DOWN);
+  generator.ReleaseKey(ui::VKEY_TAB, ui::EF_ALT_DOWN);
+  EXPECT_TRUE(wm::GetWindowState(w1.get())->IsActive());
+
+  // Because w1 is full-screen, the event should be passed to the browser
+  // window to handle it (which if the browser doesn't handle it will pass on
+  // the alt+tab to continue cycling).
+  KeyEventCounter key_count;
+  w1->AddPreTargetHandler(&key_count);
+  generator.PressKey(ui::VKEY_TAB, ui::EF_ALT_DOWN);
+  EXPECT_EQ(1u, key_count.GetCountAndReset());
+}
+
 }  // namespace ash