Have Dictation stop when focus changes

With this change, Dictation stops listening when a new tab is opened, as
well as in most cases where focus changes between two text fields on a
page.

I will follow up on why it does not stop when using my minimal example
of two <input type='text'> tags (and nothing else).

Bug: 866489
Change-Id: Ib0a60dcb3b5871173bceeab9675491c81e72414d
Reviewed-on: https://chromium-review.googlesource.com/c/1347002Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Reviewed-by: Katie Dektar <katie@chromium.org>
Commit-Queue: Anastasia Helfinstein <anastasi@google.com>
Cr-Commit-Position: refs/heads/master@{#610899}

chrome/browser/chromeos/accessibility/dictation_chromeos.cc

@@ -61,9 +61,15 @@ ui::IMEInputContextHandlerInterface* GetInputContext() {
 DictationChromeos::DictationChromeos(Profile* profile)
     : composition_(std::make_unique<ui::CompositionText>()),
       profile_(profile),
-      weak_ptr_factory_(this) {}
+      weak_ptr_factory_(this) {
+  if (GetInputContext() && GetInputContext()->GetInputMethod())
+    GetInputContext()->GetInputMethod()->AddObserver(this);
+}
 
-DictationChromeos::~DictationChromeos() = default;
+DictationChromeos::~DictationChromeos() {
+  if (GetInputContext() && GetInputContext()->GetInputMethod())
+    GetInputContext()->GetInputMethod()->RemoveObserver(this);
+}
 
 bool DictationChromeos::OnToggleDictation() {
   if (speech_recognizer_) {
@@ -113,6 +119,18 @@ void DictationChromeos::OnSpeechRecognitionStateChanged(
 void DictationChromeos::GetSpeechAuthParameters(std::string* auth_scope,
                                                 std::string* auth_token) {}
 
+void DictationChromeos::OnTextInputStateChanged(
+    const ui::TextInputClient* client) {
+  if (!client)
+    return;
+
+  if (client->GetFocusReason() ==
+      ui::TextInputClient::FocusReason::FOCUS_REASON_NONE)
+    return;
+
+  DictationOff();
+}
+
 void DictationChromeos::DictationOff() {
   if (!speech_recognizer_)
     return;

chrome/browser/chromeos/accessibility/dictation_chromeos.h

@@ -11,9 +11,11 @@
 #include "base/memory/weak_ptr.h"
 #include "chrome/browser/speech/speech_recognizer_delegate.h"
 #include "content/public/browser/speech_recognition_session_preamble.h"
+#include "ui/base/ime/input_method_observer.h"
 
 namespace ui {
 struct CompositionText;
+class TextInputClient;
 }  // namespace ui
 
 class Profile;
@@ -22,7 +24,8 @@ class SpeechRecognizer;
 namespace chromeos {
 
 // Provides global dictation (type what you speak) on Chrome OS.
-class DictationChromeos : public SpeechRecognizerDelegate {
+class DictationChromeos : public SpeechRecognizerDelegate,
+                          public ui::InputMethodObserver {
  public:
   explicit DictationChromeos(Profile* profile);
   ~DictationChromeos() override;
@@ -41,6 +44,14 @@ class DictationChromeos : public SpeechRecognizerDelegate {
   void GetSpeechAuthParameters(std::string* auth_scope,
                                std::string* auth_token) override;
 
+  // ui::InputMethodObserver:
+  void OnTextInputStateChanged(const ui::TextInputClient* client) override;
+  void OnCaretBoundsChanged(const ui::TextInputClient* client) override {}
+  void OnInputMethodDestroyed(const ui::InputMethod* input_method) override {}
+  void OnShowVirtualKeyboardIfEnabled() override {}
+  void OnFocus() override {}
+  void OnBlur() override {}
+
   // Saves current dictation result and stops listening.
   void DictationOff();
 

chrome/browser/chromeos/accessibility/dictation_chromeos_browsertest.cc

@@ -6,7 +6,9 @@
 #include "chrome/browser/chromeos/accessibility/accessibility_manager.h"
 #include "chrome/browser/chromeos/accessibility/dictation_chromeos.h"
 #include "chrome/test/base/in_process_browser_test.h"
+#include "ui/base/ime/dummy_text_input_client.h"
 #include "ui/base/ime/ime_bridge.h"
+#include "ui/base/ime/input_method_base.h"
 #include "ui/base/ime/mock_ime_input_context_handler.h"
 
 namespace chromeos {
@@ -42,6 +44,10 @@ class DictationTest : public InProcessBrowserTest {
                                              is_final);
   }
 
+  void NotifyTextInputStateChanged(ui::TextInputClient* client) {
+    GetManager()->dictation_->OnTextInputStateChanged(client);
+  }
+
   ui::CompositionText GetLastCompositionText() {
     return input_context_handler_->last_update_composition_arg()
         .composition_text;
@@ -145,4 +151,19 @@ IN_PROC_BROWSER_TEST_F(DictationTest, SwitchInputContext) {
   ui::IMEBridge::Get()->SetInputContextHandler(nullptr);
 }
 
+IN_PROC_BROWSER_TEST_F(DictationTest, ChangeInputField) {
+  // Turn on dictation and start speaking.
+  AccessibilityManager::Get()->ToggleDictation();
+  SendSpeechResult(kFinalSpeechResult, false /* is_final */);
+
+  // Change the input state to a new client.
+  std::unique_ptr<ui::TextInputClient> new_client =
+      std::make_unique<ui::DummyTextInputClient>();
+  NotifyTextInputStateChanged(new_client.get());
+
+  // Check that dictation has turned off.
+  EXPECT_EQ(1, input_context_handler_->commit_text_call_count());
+  EXPECT_EQ(kFinalSpeechResult, input_context_handler_->last_commit_text());
+}
+
 }  // namespace chromeos