Allow the user to cancel the capture region action, and show its active status in the tray.

ash/common/system/chromeos/palette/tools/screenshot_unittest.cc

Index: ash/common/system/chromeos/palette/tools/screenshot_unittest.cc
diff --git a/ash/common/system/chromeos/palette/tools/screenshot_unittest.cc b/ash/common/system/chromeos/palette/tools/screenshot_unittest.cc
index ad932980463b4855377a077ab1673913dc7b50ef..4e3fe4ceb89294772c71c4d10fb966f730edaafe 100644
--- a/ash/common/system/chromeos/palette/tools/screenshot_unittest.cc
+++ b/ash/common/system/chromeos/palette/tools/screenshot_unittest.cc
@@ -5,7 +5,7 @@
 #include "ash/common/system/chromeos/palette/mock_palette_tool_delegate.h"
 #include "ash/common/system/chromeos/palette/palette_ids.h"
 #include "ash/common/system/chromeos/palette/palette_tool.h"
-#include "ash/common/system/chromeos/palette/tools/capture_region_action.h"
+#include "ash/common/system/chromeos/palette/tools/capture_region_mode.h"
 #include "ash/common/system/chromeos/palette/tools/capture_screen_action.h"
 #include "ash/common/test/test_palette_delegate.h"
 #include "ash/common/wm_shell.h"
@@ -47,15 +47,23 @@ class ScreenshotToolTest : public test::AshTestBase {
 }  // namespace
 
 // Verifies that capturing a region triggers the partial screenshot delegate
-// method, disables the tool, and hides the palette.
+// method. Invoking the callback passed to the delegate disables the tool.
 TEST_F(ScreenshotToolTest, EnablingCaptureRegionCallsDelegateAndDisablesTool) {
   std::unique_ptr<PaletteTool> tool =
-      base::MakeUnique<CaptureRegionAction>(palette_tool_delegate_.get());
-  EXPECT_CALL(*palette_tool_delegate_.get(),
-              DisableTool(PaletteToolId::CAPTURE_REGION));
+      base::MakeUnique<CaptureRegionMode>(palette_tool_delegate_.get());
+
+  // Starting a partial screenshot calls the calls the palette delegate to start
+  // a screenshot session and hides the palette.
   EXPECT_CALL(*palette_tool_delegate_.get(), HidePalette());
   tool->OnEnable();
   EXPECT_EQ(1, test_palette_delegate()->take_partial_screenshot_count());
+  testing::Mock::VerifyAndClearExpectations(palette_tool_delegate_.get());
+
+  // Calling the associated callback (partial screenshot finished) will disable
+  // the tool.
+  EXPECT_CALL(*palette_tool_delegate_.get(),
+              DisableTool(PaletteToolId::CAPTURE_REGION));
+  test_palette_delegate()->partial_screenshot_done().Run();
 }
 
 // Verifies that capturing the screen triggers the screenshot delegate method,