ime: Implement commitText with cursor behavior for web inputs.

Bug: b/174588692
Change-Id: I37c08ef6977cacd50045209a867048bdbc2d2f8e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2583666Reviewed-by: Sadrul Chowdhury <sadrul@chromium.org>
Commit-Queue: Darren Shen <shend@chromium.org>
Cr-Commit-Position: refs/heads/master@{#837381}

content/browser/renderer_host/render_widget_host_view_aura.cc

@@ -1146,9 +1146,13 @@ void RenderWidgetHostViewAura::InsertText(
 
   if (text_input_manager_ && text_input_manager_->GetActiveWidget()) {
     if (text.length()) {
-      // TODO(crbug.com/1155331): Handle |cursor_behavior| correctly.
+      const int relative_cursor_position =
+          cursor_behavior == InsertTextCursorBehavior::kMoveCursorBeforeText
+              ? -text.length()
+              : 0;
       text_input_manager_->GetActiveWidget()->ImeCommitText(
-          text, std::vector<ui::ImeTextSpan>(), gfx::Range::InvalidRange(), 0);
+          text, std::vector<ui::ImeTextSpan>(), gfx::Range::InvalidRange(),
+          relative_cursor_position);
     } else if (has_composition_text_) {
       text_input_manager_->GetActiveWidget()->ImeFinishComposingText(false);
     }

content/browser/renderer_host/render_widget_host_view_aura_unittest.cc

@@ -6025,6 +6025,28 @@ TEST_F(InputMethodResultAuraTest, CommitText) {
   }
 }
 
+TEST_F(InputMethodResultAuraTest, CommitTextBeforeCursor) {
+  base::RepeatingClosure ime_call = base::BindRepeating(
+      &ui::TextInputClient::InsertText, base::Unretained(text_input_client()),
+      base::UTF8ToUTF16("hello"),
+      ui::TextInputClient::InsertTextCursorBehavior::kMoveCursorBeforeText);
+  for (auto index : active_view_sequence_) {
+    ActivateViewForTextInputManager(views_[index], ui::TEXT_INPUT_TYPE_TEXT);
+    ime_call.Run();
+    base::RunLoop().RunUntilIdle();
+
+    MockWidgetInputHandler::MessageVector events =
+        widget_hosts_[index]->input_handler()->GetAndResetDispatchedMessages();
+    EXPECT_EQ("CommitText", GetMessageNames(events));
+
+    MockWidgetInputHandler::DispatchedIMEMessage* ime_message =
+        events[0]->ToIME();
+    EXPECT_TRUE(ime_message);
+    EXPECT_TRUE(ime_message->Matches(base::ASCIIToUTF16("hello"), {},
+                                     gfx::Range::InvalidRange(), -5, -5));
+  }
+}
+
 // This test is for RenderWidgetHostViewAura::FinishImeCompositionSession which
 // is in response to a mouse click during an ongoing composition.
 TEST_F(InputMethodResultAuraTest, FinishImeCompositionSession) {

ui/base/ime/text_input_client.h

@@ -87,6 +87,9 @@ class COMPONENT_EXPORT(UI_BASE_IME) TextInputClient {
     // Move cursor to the position after the last character in the text.
     // e.g. for "hello", the cursor will be right after "o".
     kMoveCursorAfterText,
+    // Move cursor to the position before the first character in the text.
+    // e.g. for "hello", the cursor will be right before "h".
+    kMoveCursorBeforeText,
   };
 
   // Inserts a given text at the insertion point. Current composition text or