Revert "[chromecast] Enable element focus for WebContentController"

This reverts commit ffc6f22e.

Reason for revert: key events cannot reach its target with this change. Particular app cannot adjust volume via button.

Bug: Internal b/162242786
Test: manual on device

Original change's description:
> [chromecast] Enable element focus for WebContentController
> 
> Focus did not work due to two distinct problems, both of which caused
> page-level focus to be absent, which in turn meant that blink-level
> focus was suppressed.
> 
> - The aura::Window on which focus was attempted does not have an
>   OnWindowFocused observer. This change focuses the Window that does.
> 
> - Wayland app's aura::Windows are not visible. This change adds a check
>   for an ancestor that is an exo window.
> 
> Bug: b/156123509
> Test: manual on device
> Change-Id: Ib4e8a5101bbc28d2b7a0448aff8142c8cffa2a76
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2274201
> Reviewed-by: Daniele Castagna <dcastagna@chromium.org>
> Reviewed-by: Daniel Nicoara <dnicoara@chromium.org>
> Reviewed-by: Albert Chaulk <achaulk@chromium.org>
> Commit-Queue: Kevin Schoedel <kpschoedel@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#786469}

TBR=achaulk@chromium.org,dnicoara@chromium.org,kpschoedel@chromium.org,dcastagna@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: b/156123509
Change-Id: Ifd988ad2469c2797d43e74c9194f2b28b7c31753
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2335395
Commit-Queue: Jiawei Li <lijiawei@chromium.org>
Reviewed-by: Luke Halliwell (slow) <halliwell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#794641}

chromecast/browser/webview/web_content_controller.cc

@@ -12,7 +12,6 @@
 #include "chromecast/browser/cast_web_contents.h"
 #include "chromecast/browser/webview/proto/webview.pb.h"
 #include "chromecast/browser/webview/webview_navigation_throttle.h"
-#include "chromecast/graphics/cast_focus_client_aura.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/browsing_data_remover.h"
 #include "content/public/browser/navigation_handle.h"
@@ -181,23 +180,14 @@ void WebContentController::AttachTo(aura::Window* window, int window_id) {
 void WebContentController::ProcessInputEvent(const webview::InputEvent& ev) {
   content::WebContents* contents = GetWebContents();
   DCHECK(contents);
-
-  // Ensure this web contents has focus before sending it input.
-  // Focus at this level is necessary, or else Blink will ignore
-  // attempts to focus any elements in the contents.
-  //
-  // Via b/156123509: The aura::Window given by |contents->GetNativeView()|
-  // is not suitable for this purpose, because it has no OnWindowFocused
-  // observer. The |window| used here is the same one whose |delegate|
-  // is the EventHandler for this input event.
-  content::RenderWidgetHostView* rwhv = contents->GetRenderWidgetHostView();
-  aura::Window* window = rwhv->GetNativeView();
-  DCHECK(window == contents->GetContentNativeView());
-  if (!window->CanFocus())
+  DCHECK(contents->GetNativeView());
+  if (!contents->GetNativeView()->CanFocus())
     return;
-  if (!window->HasFocus())
-    window->Focus();
+  // Ensure this web contents has focus before sending it input.
+  if (!contents->GetNativeView()->HasFocus())
+    contents->GetNativeView()->Focus();
 
+  content::RenderWidgetHostView* rwhv = contents->GetRenderWidgetHostView();
   ui::EventHandler* handler = rwhv->GetNativeView()->delegate();
   ui::EventType type = static_cast<ui::EventType>(ev.event_type());
   switch (type) {

chromecast/graphics/BUILD.gn

@@ -108,10 +108,7 @@ cast_source_set("graphics") {
   }
 
   if (use_ozone) {
-    deps += [
-      "//components/exo",
-      "//ui/ozone",
-    ]
+    deps += [ "//ui/ozone" ]
   }
 }
 

chromecast/graphics/cast_focus_client_aura.cc

@@ -6,7 +6,6 @@
 
 #include "base/logging.h"
 #include "base/stl_util.h"
-#include "components/exo/surface.h"
 #include "ui/aura/window.h"
 
 #define LOG_WINDOW_INFO(top_level, window)                              \
@@ -14,19 +13,6 @@
                 << "', window: " << (window)->id() << ": '"             \
                 << (window)->GetName() << "'"
 
-namespace {
-
-bool IsVisibleExoWindow(aura::Window* window) {
-  for (aura::Window* w = window; w; w = w->parent()) {
-    if (w->GetProperty(exo::kClientSurfaceIdKey) && w->IsVisible()) {
-      return true;
-    }
-  }
-  return false;
-}
-
-}  // namespace
-
 namespace chromecast {
 
 CastFocusClientAura::CastFocusClientAura() : focused_window_(nullptr) {}
@@ -207,10 +193,7 @@ aura::Window* CastFocusClientAura::GetWindowToFocus() {
   aura::Window* next = nullptr;
   aura::Window* next_top_level = nullptr;
   for (aura::Window* window : focusable_windows_) {
-    if (!window->CanFocus()) {
-      continue;
-    }
-    if (!window->IsVisible() && !IsVisibleExoWindow(window)) {
+    if (!window->CanFocus() || !window->IsVisible()) {
       continue;
     }