Converts focusmanager from delegate to observer

components/mus/ws/BUILD.gn

Index: components/mus/ws/BUILD.gn
diff --git a/components/mus/ws/BUILD.gn b/components/mus/ws/BUILD.gn
index e7f92231961bbfc78208b4e6ceac96dade2437a9..1080f41a4373ce0395632d9ef2d3fa460f941a39 100644
--- a/components/mus/ws/BUILD.gn
+++ b/components/mus/ws/BUILD.gn
@@ -27,7 +27,7 @@ source_set("lib") {
     "event_dispatcher_delegate.h",
     "focus_controller.cc",
     "focus_controller.h",
-    "focus_controller_delegate.h",
+    "focus_controller_observer.h",
     "forwarding_window_manager.cc",
     "forwarding_window_manager.h",
     "operation.cc",
@@ -64,7 +64,7 @@ source_set("lib") {
     "//cc/surfaces",
     "//cc/surfaces:surface_id",
     "//components/mus/common",
-    "//components/mus/gles2:gles2",
+    "//components/mus/gles2",
     "//components/mus/public/interfaces",
     "//components/mus/surfaces",
     "//mojo/application/public/cpp",
@@ -79,10 +79,10 @@ source_set("lib") {
     "//ui/events/platform",
     "//ui/gfx",
     "//ui/gfx/geometry",
-    "//ui/gl:gl",
+    "//ui/gl",
     "//ui/mojo/geometry:interfaces",
+    "//ui/platform_window",
     "//ui/platform_window:platform_impls",
-    "//ui/platform_window:platform_window",
   ]
 }
 
@@ -127,14 +127,14 @@ test("window_manager_unittests") {
   ]
 
   deps = [
-    ":test_support",
     ":lib",
+    ":test_support",
     "//base",
     "//base/test:test_config",
     "//components/mus/common",
-    "//components/mus/surfaces",
     "//components/mus/public/cpp",
     "//components/mus/public/interfaces",
+    "//components/mus/surfaces",
     "//mojo/application/public/interfaces",
     "//mojo/converters/geometry",
     "//mojo/converters/input_events",
@@ -143,13 +143,13 @@ test("window_manager_unittests") {
     "//mojo/gles2",
     "//mojo/platform_handle",
     "//mojo/public/cpp/bindings:bindings",
-    "//third_party/mojo/src/mojo/edk/test:run_all_unittests",
-    "//ui/mojo/geometry:interfaces",
     "//testing/gtest",
+    "//third_party/mojo/src/mojo/edk/test:run_all_unittests",
     "//ui/events",
     "//ui/gfx",
     "//ui/gfx:test_support",
     "//ui/gfx/geometry",
+    "//ui/mojo/geometry:interfaces",
   ]
 
   if (!is_android) {  # TODO(GYP) Enable on Android when osmesa links.