Revert "Always inject mocks for more hemertic InputMethodManagerImpl unit tests."

This reverts commit 2b9c5c7c.

Reason for revert: This CL is likely the root cause for build failure for linux-chromeos-dbg, starting from https://ci.chromium.org/p/chromium/builders/ci/linux-chromeos-dbg/21474
The failed tests are: InputMethodManagerImplTest.SetLoginDefaultWithAllowedKeyboardLayouts
InputMethodManagerImplTest.TestEnableLayoutsNonUsHardwareKeyboard
InputMethodManagerImplTest.TestEnableMultipleHardwareKeyboardLayout

Original change's description:
> Always inject mocks for more hemertic InputMethodManagerImpl unit tests.
>
> Six InputMethodManagerImpl tests are failing in specific environments
> due to mixed usage of test data and CrOS prod configs. Partly caused by
> inconsistent usage of MockComponentExtensionIMEDelegateManager. In
> particular, parts of Setup() are run without this mock injected. The fix
> here ensures the mock and its test data are consistently used throughout.
>
> With this we manage to un-fail 4 out of 6 tests, but another new test
> starts failing! It's unsurprising because these tests still indirectly
> depend on deprecated input_methods.txt configs (remnant from before the
> migration to extension-based input methods circa 2011). This issue will
> be addressed in the next steps.
>
> Bug: 970790
> Change-Id: I3e76708e34f2b4e021f763654714d157f48a3925
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2550152
> Commit-Queue: Bao-Duy Tran <tranbaoduy@chromium.org>
> Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
> Reviewed-by: John Palmer <jopalmer@chromium.org>
> Reviewed-by: Darren Shen <shend@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#831198}

TBR=ynovikov@chromium.org,shend@chromium.org,tranbaoduy@chromium.org,jopalmer@chromium.org

Change-Id: I4fea5ebf6f46f66ba837d693f7970a0ac8949054
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 970790
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2560527Reviewed-by: Maggie Cai <mxcai@chromium.org>
Commit-Queue: Maggie Cai <mxcai@chromium.org>
Cr-Commit-Position: refs/heads/master@{#831256}

chrome/browser/chromeos/input_method/input_method_manager_impl.cc

@@ -1255,6 +1255,13 @@ void InputMethodManagerImpl::SetImeKeyboardForTesting(ImeKeyboard* keyboard) {
   keyboard_.reset(keyboard);
 }
 
+void InputMethodManagerImpl::InitializeComponentExtensionForTesting(
+    std::unique_ptr<ComponentExtensionIMEManagerDelegate> delegate) {
+  component_extension_ime_manager_->Initialize(std::move(delegate));
+  util_.ResetInputMethods(
+      component_extension_ime_manager_->GetAllIMEAsInputMethodDescriptor());
+}
+
 void InputMethodManagerImpl::Observe(
     int type,
     const content::NotificationSource& source,

chrome/browser/chromeos/input_method/input_method_manager_impl.h

@@ -249,6 +249,9 @@ class InputMethodManagerImpl : public InputMethodManager,
       CandidateWindowController* candidate_window_controller);
   // Sets |keyboard_|.
   void SetImeKeyboardForTesting(ImeKeyboard* keyboard);
+  // Initialize |component_extension_manager_|.
+  void InitializeComponentExtensionForTesting(
+      std::unique_ptr<ComponentExtensionIMEManagerDelegate> delegate);
 
   // content::NotificationObserver overrides:
   void Observe(int type,

chrome/browser/chromeos/input_method/input_method_manager_impl_unittest.cc

@@ -17,6 +17,7 @@
 #include "base/macros.h"
 #include "base/run_loop.h"
 #include "base/test/task_environment.h"
+#include "chrome/browser/chromeos/input_method/component_extension_ime_manager_delegate_impl.h"
 #include "chrome/browser/chromeos/input_method/mock_candidate_window_controller.h"
 #include "chrome/browser/chromeos/input_method/mock_input_method_engine.h"
 #include "chrome/browser/profiles/profile_manager.h"
@@ -138,15 +139,9 @@ class InputMethodManagerImplTest :  public BrowserWithTestWindowTest {
   void SetUp() override {
     ui::InitializeInputMethodForTesting();
 
-    InitImeList();
-
-    auto mock_delegate =
-        std::make_unique<MockComponentExtensionIMEManagerDelegate>();
-    mock_delegate->set_ime_list(ime_list_);
-
     manager_ = std::make_unique<InputMethodManagerImpl>(
-        std::make_unique<FakeInputMethodDelegate>(), std::move(mock_delegate),
-        false);
+        std::make_unique<FakeInputMethodDelegate>(),
+        std::make_unique<ComponentExtensionIMEManagerDelegateImpl>(), false);
     manager_->GetInputMethodUtil()->UpdateHardwareLayoutCache();
     candidate_window_controller_ = new MockCandidateWindowController;
     manager_->SetCandidateWindowControllerForTesting(
@@ -159,12 +154,32 @@ class InputMethodManagerImplTest :  public BrowserWithTestWindowTest {
 
     menu_manager_ = ui::ime::InputMethodMenuManager::GetInstance();
 
+    InitImeList();
+
     BrowserWithTestWindowTest::SetUp();
 
     // Needs ash::Shell keyboard to be created first.
     chrome_keyboard_controller_client_test_helper_ =
         ChromeKeyboardControllerClientTestHelper::InitializeForAsh();
 
+    InitComponentExtension();
+  }
+
+  void TearDown() override {
+    // Needs to destroyed before ash::Shell keyboard.
+    chrome_keyboard_controller_client_test_helper_.reset();
+
+    BrowserWithTestWindowTest::TearDown();
+    ui::ShutdownInputMethodForTesting();
+
+    candidate_window_controller_ = nullptr;
+    keyboard_ = nullptr;
+    manager_.reset();
+  }
+
+ private:
+  // Helper function to initialize component extension stuff for testing.
+  void InitComponentExtension() {
     // CreateNewState(nullptr) returns state with non-empty
     // current_input_method. So SetState() triggers ChangeInputMethod().
     InputMethodDescriptors descriptors;
@@ -177,18 +192,17 @@ class InputMethodManagerImplTest :  public BrowserWithTestWindowTest {
     state->AddInputMethodExtension(extension_ime_util::kT13nExtensionId,
                                    descriptors, mock_engine_handler_.get());
     manager_->SetState(state);
-  }
-
-  void TearDown() override {
-    // Needs to destroyed before ash::Shell keyboard.
-    chrome_keyboard_controller_client_test_helper_.reset();
 
-    BrowserWithTestWindowTest::TearDown();
-    ui::ShutdownInputMethodForTesting();
+    MockComponentExtensionIMEManagerDelegate* mock_delegate =
+        new MockComponentExtensionIMEManagerDelegate();
+    mock_delegate->set_ime_list(ime_list_);
+    std::unique_ptr<ComponentExtensionIMEManagerDelegate> delegate(
+        mock_delegate);
 
-    candidate_window_controller_ = nullptr;
-    keyboard_ = nullptr;
-    manager_.reset();
+    // Note, for production, these SetEngineHandler are called when
+    // IMEEngineHandlerInterface is initialized via
+    // InitializeComponentextension.
+    manager_->InitializeComponentExtensionForTesting(std::move(delegate));
   }
 
   void InitImeList() {

testing/buildbot/chromium.chromiumos.json

@@ -4402,9 +4402,6 @@
         "test_id_prefix": "ninja://ui/touch_selection:ui_touch_selection_unittests/"
       },
       {
-        "args": [
-          "--test-launcher-filter-file=../../testing/buildbot/filters/chromeos.unit_tests.filter"
-        ],
         "isolate_profile_data": true,
         "merge": {
           "args": [],

testing/buildbot/filters/chromeos.unit_tests.filter

 # TODO(crbug.com/970790): Enable this.
--InputMethodManagerImplTest.SetLoginDefaultWithAllowedKeyboardLayouts
+-InputMethodManagerImplTest.TestEnableLayouts
 -InputMethodManagerImplTest.TestEnableLayoutsNonUsHardwareKeyboard
 -InputMethodManagerImplTest.TestEnableMultipleHardwareKeyboardLayout
+-InputMethodManagerImplTest.TestLastUsedInputMethod
+-InputMethodManagerImplTest.TestNextInputMethod
+-InputMethodManagerImplTest.TestObserver
 # TODO(crbug.com/970806): Enable this.
 -KeyboardShortcutViewerMetadataTest.ModifyAcceleratorShouldUpdateMetadata

testing/buildbot/test_suite_exceptions.pyl

@@ -2761,9 +2761,6 @@
         },
       },
       'linux-chromeos-rel': {
-        'args': [
-          '--test-launcher-filter-file=../../testing/buildbot/filters/chromeos.unit_tests.filter',
-        ],
         'swarming': {
           'shards': 2,
         },