Eliminate test dependency brought by EventGenerator::PressTouch

EventGenerator::PressTouch would set |is_touch_down_| of aura::Env to
be true. And aura::Env is singleton and shared by test cases. So in CL,
AshTestBase::SetUp is modified to reset aura::Env's properties.

Bug: 586514
Change-Id: Iea96d7fcfc2fba1db857e0d8fe7a1931300cf0cd
Reviewed-on: https://chromium-review.googlesource.com/c/1293174Reviewed-by: Sadrul Chowdhury <sadrul@chromium.org>
Reviewed-by: Mitsuru Oshima <oshima@chromium.org>
Commit-Queue: Andrew Xu <andrewxu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#604745}

ash/test/ash_test_helper.cc

@@ -282,10 +282,13 @@ void AshTestHelper::SetUp(bool start_session, bool provide_local_state) {
 
   CreateShell();
 
+  // Reset aura::Env to eliminate test dependency (https://crbug.com/586514).
+  aura::test::EnvTestHelper env_helper(Shell::Get()->aura_env());
+  env_helper.ResetEnvForTesting();
+
   aura::test::SetEnvForTestWindows(Shell::Get()->aura_env());
 
-  aura::test::EnvTestHelper(Shell::Get()->aura_env())
-      .SetInputStateLookup(std::unique_ptr<aura::InputStateLookup>());
+  env_helper.SetInputStateLookup(std::unique_ptr<aura::InputStateLookup>());
 
   Shell* shell = Shell::Get();
 

ui/aura/env.cc

@@ -315,7 +315,6 @@ Env::Env(Mode mode)
     : mode_(mode),
       env_controller_(std::make_unique<EnvInputStateController>(this)),
       mouse_button_flags_(0),
-      is_touch_down_(false),
       get_last_mouse_location_from_mus_(mode_ == Mode::MUS),
       gesture_recognizer_(std::make_unique<ui::GestureRecognizerImpl>()),
       input_state_lookup_(InputStateLookup::Create()),

ui/aura/env.h

@@ -284,7 +284,7 @@ class AURA_EXPORT Env : public ui::EventTarget,
   int mouse_button_flags_;
   // Location of last mouse event, in screen coordinates.
   mutable gfx::Point last_mouse_location_;
-  bool is_touch_down_;
+  bool is_touch_down_ = false;
   bool get_last_mouse_location_from_mus_;
   // This may be set to true in tests to force using |last_mouse_location_|
   // rather than querying WindowTreeClient.

ui/aura/test/aura_test_helper.cc

@@ -134,6 +134,10 @@ void AuraTestHelper::SetUp(ui::ContextFactory* context_factory,
   }
 
   EnvTestHelper env_helper(env);
+
+  // Reset aura::Env to eliminate test dependency (https://crbug.com/586514).
+  env_helper.ResetEnvForTesting();
+
   if (env_mode == Env::Mode::MUS) {
     env_window_tree_client_setter_ =
         std::make_unique<EnvWindowTreeClientSetter>(window_tree_client_);

ui/aura/test/env_test_helper.h

@@ -67,6 +67,10 @@ class EnvTestHelper {
     env_->always_use_last_mouse_location_ = value;
   }
 
+  // Reset aura::Env to eliminate potential test dependency.
+  // (https://crbug.com/586514)
+  void ResetEnvForTesting() { env_->is_touch_down_ = false; }
+
   void SetGestureRecognizer(
       std::unique_ptr<ui::GestureRecognizer> gesture_recognizer) {
     env_->gesture_recognizer_ = std::move(gesture_recognizer);