mash cleanup: Remove ui_devtools support

Remove Ash's separate registration of root windows for SPM.
Remove UAF and root window determination workarounds for SPM.

Bug: 958471
Test: No ui_devtools regressions
Change-Id: I55fe07b83731c3832e803078eb75526972534958
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1631904Reviewed-by: Leonard Grey <lgrey@chromium.org>
Commit-Queue: Michael Wasserman <msw@chromium.org>
Cr-Commit-Position: refs/heads/master@{#664356}

chrome/browser/ui/ash/chrome_browser_main_extra_parts_ash.cc

@@ -50,8 +50,6 @@
 #include "components/session_manager/core/session_manager.h"
 #include "components/session_manager/core/session_manager_observer.h"
 #include "components/startup_metric_utils/browser/startup_metric_utils.h"
-#include "components/ui_devtools/switches.h"
-#include "components/ui_devtools/views/devtools_server_util.h"
 #include "content/public/browser/browser_task_traits.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_observer.h"
@@ -128,18 +126,6 @@ void ChromeBrowserMainExtraPartsAsh::PreProfileInit() {
 
   ash_shell_init_ = std::make_unique<AshShellInit>();
 
-  if (ui_devtools::UiDevToolsServer::IsUiDevToolsEnabled(
-          ui_devtools::switches::kEnableUiDevTools)) {
-    // Register Ash's root windows with UI DevTools; warn in multi-process Mash.
-    // TODO(crbug.com/896977): Refine ui_devtools support for Ash and mojo apps.
-    if (features::IsSingleProcessMash()) {
-      ui_devtools::RegisterAdditionalRootWindowsAndEnv(
-          ash::Shell::Get()->GetAllRootWindows());
-    } else if (features::IsMultiProcessMash()) {
-      LOG(WARNING) << "Chrome cannot access Ash and mojo app UIs in Mash.";
-    }
-  }
-
   screen_orientation_delegate_ =
       std::make_unique<ScreenOrientationDelegateChromeos>();
 

chrome/browser/ui/views/chrome_browser_main_extra_parts_views.cc

@@ -82,8 +82,7 @@ void ChromeBrowserMainExtraPartsViews::PreCreateThreads() {
 void ChromeBrowserMainExtraPartsViews::PreProfileInit() {
   if (ui_devtools::UiDevToolsServer::IsUiDevToolsEnabled(
           ui_devtools::switches::kEnableUiDevTools)) {
-    // Starts the UI Devtools server for the browser UI. On Aura platforms,
-    // ChromeBrowserMainExtraPartsAsh wires up Ash UI for SingleProcessMash.
+    // Starts the UI Devtools server for browser UI (and Ash UI on Chrome OS).
     devtools_server_ = ui_devtools::CreateUiDevToolsServerForViews(
         g_browser_process->system_network_context_manager()->GetContext());
   }
@@ -133,13 +132,4 @@ void ChromeBrowserMainExtraPartsViews::PostMainMessageLoopRun() {
   // down explicitly here to avoid a case where such an event arrives during
   // shutdown.
   relaunch_notification_controller_.reset();
-
-#if defined(USE_AURA)
-  // Explicitly release |devtools_server_| to avoid use-after-free under
-  // single process mash, where |devtools_server_| indirectly accesses
-  // the Env of ash::Shell during destruction and ash::Shell as part of
-  // ChromeBrowserMainExtraPartsAsh is released before
-  // ChromeBrowserMainExtraPartsViews.
-  devtools_server_.reset();
-#endif
 }

components/ui_devtools/views/devtools_server_util.cc

@@ -6,19 +6,12 @@
 
 #include <memory>
 
-#include "base/command_line.h"
-#include "build/build_config.h"
 #include "components/ui_devtools/css_agent.h"
 #include "components/ui_devtools/devtools_server.h"
 #include "components/ui_devtools/switches.h"
 #include "components/ui_devtools/views/dom_agent_views.h"
 #include "components/ui_devtools/views/overlay_agent_views.h"
 
-#if defined(USE_AURA)
-#include "components/ui_devtools/views/dom_agent_aura.h"
-#include "components/ui_devtools/views/overlay_agent_aura.h"
-#endif
-
 namespace ui_devtools {
 
 std::unique_ptr<UiDevToolsServer> CreateUiDevToolsServerForViews(
@@ -39,12 +32,4 @@ std::unique_ptr<UiDevToolsServer> CreateUiDevToolsServerForViews(
   return server;
 }
 
-#if defined(USE_AURA)
-void RegisterAdditionalRootWindowsAndEnv(std::vector<aura::Window*> roots) {
-  DCHECK(!roots.empty());
-  for (auto* root : roots)
-    DOMAgentAura::GetInstance()->RegisterRootWindow(root);
-}
-#endif
-
 }  // namespace ui_devtools

components/ui_devtools/views/devtools_server_util.h

@@ -6,23 +6,15 @@
 #define COMPONENTS_UI_DEVTOOLS_VIEWS_DEVTOOLS_SERVER_UTIL_H_
 
 #include <memory>
-#include <vector>
 
 #include "components/ui_devtools/devtools_server.h"
 
-namespace aura {
-class Window;
-}
-
 namespace ui_devtools {
 
 // A factory helper to construct a UiDevToolsServer for Views.
 std::unique_ptr<UiDevToolsServer> CreateUiDevToolsServerForViews(
     network::mojom::NetworkContext* network_context);
 
-// Register additional root windows and wire up their Aura Env.
-void RegisterAdditionalRootWindowsAndEnv(std::vector<aura::Window*> roots);
-
 }  // namespace ui_devtools
 
 #endif  // COMPONENTS_UI_DEVTOOLS_VIEWS_DEVTOOLS_SERVER_UTIL_H_

components/ui_devtools/views/dom_agent_aura.cc

@@ -25,6 +25,7 @@ DOMAgentAura::DOMAgentAura() {
   dom_agent_aura_ = this;
   aura::Env::GetInstance()->AddObserver(this);
 }
+
 DOMAgentAura::~DOMAgentAura() {
   for (aura::Window* window : roots_)
     window->RemoveObserver(this);
@@ -32,13 +33,9 @@ DOMAgentAura::~DOMAgentAura() {
   dom_agent_aura_ = nullptr;
 }
 
-void DOMAgentAura::RegisterRootWindow(aura::Window* root) {
-  roots_.push_back(root);
-  root->AddObserver(this);
-}
-
 void DOMAgentAura::OnHostInitialized(aura::WindowTreeHost* host) {
-  RegisterRootWindow(host->window());
+  roots_.push_back(host->window());
+  host->window()->AddObserver(this);
 }
 
 void DOMAgentAura::OnWindowDestroying(aura::Window* window) {

components/ui_devtools/views/dom_agent_aura.h

@@ -24,7 +24,6 @@ class DOMAgentAura : public DOMAgentViews,
 
   ~DOMAgentAura() override;
   static DOMAgentAura* GetInstance() { return dom_agent_aura_; }
-  void RegisterRootWindow(aura::Window* root);
 
   // DOMAgent
   std::vector<UIElement*> CreateChildrenForRoot() override;

components/ui_devtools/views/overlay_agent_aura.cc

@@ -4,6 +4,7 @@
 
 #include "components/ui_devtools/views/overlay_agent_aura.h"
 
+#include "components/ui_devtools/dom_agent.h"
 #include "components/ui_devtools/views/window_element.h"
 #include "ui/aura/env.h"
 #include "ui/views/view.h"

components/ui_devtools/views/overlay_agent_aura.h

@@ -7,19 +7,14 @@
 
 #include "components/ui_devtools/views/overlay_agent_views.h"
 
-#include "components/ui_devtools/dom_agent.h"
-
-namespace aura {
-class Env;
-}
-
 namespace ui_devtools {
 
+class DOMAgent;
+
 class OverlayAgentAura : public OverlayAgentViews {
  public:
   OverlayAgentAura(DOMAgent* dom_agent);
   ~OverlayAgentAura() override;
-  void RegisterEnv(aura::Env* env);
 
   int FindElementIdTargetedByPoint(ui::LocatedEvent* event) const override;
   static OverlayAgentAura* GetInstance() { return overlay_agent_aura_; }

components/ui_devtools/views/overlay_agent_views.cc

@@ -12,8 +12,6 @@
 #include "third_party/skia/include/core/SkColor.h"
 #include "third_party/skia/include/effects/SkDashPathEffect.h"
 #include "ui/compositor/paint_recorder.h"
-#include "ui/display/display.h"
-#include "ui/display/screen.h"
 #include "ui/events/event.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/geometry/rect_conversions.h"
@@ -719,14 +717,6 @@ bool OverlayAgentViews::UpdateHighlight(
 #else
   gfx::NativeWindow root = window_and_bounds.first->GetRootWindow();
   root_layer = root->layer();
-#if defined(OS_CHROMEOS)
-  // Get the screen's display-root window; otherwise, if the window belongs to
-  // a window service client, |root| will only be a client-root window.
-  aura::Window* window = display::Screen::GetScreen()->GetWindowAtScreenPoint(
-      root->GetBoundsInScreen().origin());
-  if (window)  // May be null in unit tests.
-    root = window->GetRootWindow();
-#endif  // OS_CHROMEOS
   layer_for_highlighting_screen_offset_ =
       root->GetBoundsInScreen().OffsetFromOrigin();
 #endif  // defined(OS_MACOSX)