[IME] Fix s_suppressNextKeypressEvent logic in WebViewImpl::setComposition().

Source/web/tests/WebViewTest.cpp

 /*
  * Copyright (C) 2011, 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 1414 matching lines @@
     // Clear the focus and track that the subsequent composition commit does not trigger a
     // text changed notification for autofill.
     client.clearChangeCounts();
     webView->setFocus(false);
     EXPECT_EQ(1, client.textChangesWhileIgnored());
     EXPECT_EQ(0, client.textChangesWhileNotIgnored());
 
     frame->setAutofillClient(0);
 }
 
+static void verifySelectionAndComposition(WebView* webView, int selectionStart, int selectionEnd, int compositionStart, int compositionEnd, const char* failMessage)
+{
+    WebTextInputInfo info = webView->textInputInfo();
+    EXPECT_EQ(selectionStart, info.selectionStart) << failMessage;
+    EXPECT_EQ(selectionEnd, info.selectionEnd) << failMessage;
+    EXPECT_EQ(compositionStart, info.compositionStart) << failMessage;
+    EXPECT_EQ(compositionEnd, info.compositionEnd) << failMessage;
+}
+
+TEST_F(WebViewTest, CompositionNotCancelledByBackspace)
+{
+    URLTestHelpers::registerMockedURLFromBaseURL(WebString::fromUTF8(m_baseURL.c_str()), WebString::fromUTF8("composition_not_cancelled_by_backspace.html"));
+    MockAutofillClient client;
+    WebView* webView = m_webViewHelper.initializeAndLoad(m_baseURL + "composition_not_cancelled_by_backspace.html");
+    WebLocalFrameImpl* frame = toWebLocalFrameImpl(webView->mainFrame());
+    frame->setAutofillClient(&client);
+    webView->setInitialFocus(false);
+
+    // Test both input elements.
+    for (int i = 0; i < 2; ++i) {
+        // Select composition and do sanity check.
+        WebVector<WebCompositionUnderline> emptyUnderlines;
+        frame->setEditableSelectionOffsets(6, 6);
+        EXPECT_TRUE(webView->setComposition("fghij", emptyUnderlines, 0, 5));
+        frame->setEditableSelectionOffsets(11, 11);
+        verifySelectionAndComposition(webView, 11, 11, 6, 11, "initial case");
+
+        // Press Backspace and verify composition didn't get cancelled. This is to verify the fix
+        // for crbug.com/429916.
+        WebKeyboardEvent keyEvent;
+        keyEvent.windowsKeyCode = VKEY_BACK;
+        keyEvent.setKeyIdentifierFromWindowsKeyCode();
+        keyEvent.type = WebInputEvent::RawKeyDown;
+        webView->handleInputEvent(keyEvent);
+
+        frame->setEditableSelectionOffsets(6, 6);
+        EXPECT_TRUE(webView->setComposition("fghi", emptyUnderlines, 0, 4));
+        frame->setEditableSelectionOffsets(10, 10);
+        verifySelectionAndComposition(webView, 10, 10, 6, 10, "after pressing Backspace");
+
+        keyEvent.type = WebInputEvent::KeyUp;
+        webView->handleInputEvent(keyEvent);
+
+        webView->advanceFocus(false);
+    }
+
+    frame->setAutofillClient(0);
+}
+
 TEST_F(WebViewTest, ConfirmCompositionTriggersAutofillTextChange)
 {
     URLTestHelpers::registerMockedURLFromBaseURL(WebString::fromUTF8(m_baseURL.c_str()), WebString::fromUTF8("input_field_populated.html"));
     MockAutofillClient client;
     WebView* webView = m_webViewHelper.initializeAndLoad(m_baseURL + "input_field_populated.html");
     WebLocalFrameImpl* frame = toWebLocalFrameImpl(webView->mainFrame());
     frame->setAutofillClient(&client);
     webView->setInitialFocus(false);
 
     // Set up a composition that needs to be committed.
@@ skipping 944 matching lines @@
     // Test without any preventDefault.
     client.reset();
     frame->executeScript(WebScriptSource("setTest('none');"));
     EXPECT_TRUE(tapElementById(webView, WebInputEvent::GestureTap, WebString::fromUTF8("target")));
     EXPECT_TRUE(client.getWasCalled());
 
     m_webViewHelper.reset(); // Remove dependency on locally scoped client.
 }
 
 } // namespace