[IME] Use proper const in ImeAdaptor for autocomplete, updating tests.

This is a follow-up clean up to
https://chromiumcodereview.appspot.com/842493004/
so we can:
- Use the appropriate constant to detect autocomplete="off".
- Add test case for autocomplete="off" (returns key code rather than 229).

Review URL: https://codereview.chromium.org/848223003

Cr-Commit-Position: refs/heads/master@{#311773}

content/public/android/java/src/org/chromium/content/browser/input/ImeAdapter.java

@@ -426,13 +426,9 @@ public class ImeAdapter {
                                 KeyEvent.changeAction(keyEvent, KeyEvent.ACTION_UP), 0);
             }
 
-            // FIXME: Use WebTextInputFlags.AutocompleteOff. We need this hack to enable merge into
-            // into Beta to fix http://crbug.com/422685 .
-            final int textInputFlagAutocompleteOff = 1 << 1;
-
             // If we do not have autocomplete=off, then always send compose events rather than a
             // guessed keyCode. This addresses http://crbug.com/422685 .
-            if ((mTextInputFlags & textInputFlagAutocompleteOff) == 0) {
+            if ((mTextInputFlags & WebTextInputFlags.AutocompleteOff) == 0) {
                 keyCode = COMPOSITION_KEY_CODE;
                 modifiers = 0;
             }

content/public/android/javatests/src/org/chromium/content/browser/input/ImeTest.java

@@ -45,6 +45,8 @@ public class ImeTest extends ContentShellTestBase {
             + "<input id=\"input_text\" type=\"text\" /><br/>"
             + "<input id=\"input_radio\" type=\"radio\" style=\"width:50px;height:50px\" />"
             + "<br/><textarea id=\"textarea\" rows=\"4\" cols=\"20\"></textarea>"
+            + "<br/><textarea id=\"textarea2\" rows=\"4\" cols=\"20\" autocomplete=\"off\">"
+            + "</textarea>"
             + "<br/><p><span id=\"plain_text\">This is Plain Text One</span></p>"
             + "</form></body></html>");
     private static final int COMPOSITION_KEY_CODE = 229;
@@ -700,13 +702,14 @@ public class ImeTest extends ContentShellTestBase {
     @SmallTest
     @Feature({"TextInput", "Main"})
     public void testTransitionsWhileComposingText() throws Throwable {
-        DOMUtils.focusNode(mWebContents, "textarea");
+        DOMUtils.focusNode(mWebContents, "textarea");  // Default with autocomplete="on"
         assertWaitForKeyboardStatus(true);
 
         mConnection = (TestAdapterInputConnection) getAdapterInputConnection();
         waitAndVerifyEditableCallback(mConnection.mImeUpdateQueue, 0, "", 0, 0, -1, -1);
 
         // H
+        // Since autocomplete="on" by default, COMPOSITION_KEY_CODE is emitted as key code
         expectUpdateStateCall(mConnection);
         setComposingText(mConnection, "h", 1);
         assertEquals(COMPOSITION_KEY_CODE, mImeAdapter.mLastSyntheticKeyCode);
@@ -720,6 +723,30 @@ public class ImeTest extends ContentShellTestBase {
         assertEquals(COMPOSITION_KEY_CODE, mImeAdapter.mLastSyntheticKeyCode);
     }
 
+    @SmallTest
+    @Feature({"TextInput", "Main"})
+    public void testTransitionsWhileEmittingKeyCode() throws Throwable {
+        DOMUtils.focusNode(mWebContents, "textarea2");  // autocomplete="off"
+        assertWaitForKeyboardStatus(true);
+
+        mConnection = (TestAdapterInputConnection) getAdapterInputConnection();
+        waitAndVerifyEditableCallback(mConnection.mImeUpdateQueue, 0, "", 0, 0, -1, -1);
+
+        // H
+        // Since autocomplete="off", regular key codes are emitted.
+        expectUpdateStateCall(mConnection);
+        setComposingText(mConnection, "h", 1);
+        assertEquals(KeyEvent.KEYCODE_H, mImeAdapter.mLastSyntheticKeyCode);
+
+        // Simulate switch of input fields.
+        finishComposingText(mConnection);
+
+        // H
+        expectUpdateStateCall(mConnection);
+        setComposingText(mConnection, "h", 1);
+        assertEquals(KeyEvent.KEYCODE_H, mImeAdapter.mLastSyntheticKeyCode);
+    }
+
     @SmallTest
     @Feature({"TextInput"})
     public void testPastePopupShowOnLongPress() throws Throwable {