Adds a test for setting empty composition text.

ui/base/ime/dummy_text_input_client.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/base/ime/dummy_text_input_client.h"
 #include "ui/events/event.h"
 #include "ui/gfx/geometry/rect.h"
 
 namespace ui {
 
 DummyTextInputClient::DummyTextInputClient()
-    : text_input_type_(TEXT_INPUT_TYPE_NONE),
-      insert_char_count_(0),
-      insert_text_count_(0),
-      set_composition_count_(0) {}
+    : text_input_type_(TEXT_INPUT_TYPE_NONE), insert_char_count_(0) {}
 
 DummyTextInputClient::DummyTextInputClient(TextInputType text_input_type)
-    : text_input_type_(text_input_type),
-      insert_char_count_(0),
-      insert_text_count_(0),
-      set_composition_count_(0) {}
+    : text_input_type_(text_input_type), insert_char_count_(0) {}
 
 DummyTextInputClient::~DummyTextInputClient() {
 }
 
 void DummyTextInputClient::SetCompositionText(
     const CompositionText& composition) {
-  ++set_composition_count_;
-  last_composition_.CopyFrom(composition);
+  composition_history_.push_back(composition);
 }
 
 void DummyTextInputClient::ConfirmCompositionText() {
 }
 
 void DummyTextInputClient::ClearCompositionText() {
+  SetCompositionText(CompositionText());
 }
 
 void DummyTextInputClient::InsertText(const base::string16& text) {
-  ++insert_text_count_;
-  last_insert_text_ = text;
+  insert_text_history_.push_back(text);
 }
 
 void DummyTextInputClient::InsertChar(const KeyEvent& event) {
   ++insert_char_count_;
   last_insert_char_ = event.GetCharacter();
 }
 
 TextInputType DummyTextInputClient::GetTextInputType() const {
   return text_input_type_;
 }
@@ skipping 69 matching lines @@
 
 bool DummyTextInputClient::IsTextEditCommandEnabled(
     TextEditCommand command) const {
   return false;
 }
 
 void DummyTextInputClient::SetTextEditCommandForNextKeyEvent(
     TextEditCommand command) {}
 
 }  // namespace ui