Make WebView keep keyboard when losing focus

content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java

 // Copyright 2012 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.
 
 package org.chromium.content.browser;
 
 import android.annotation.SuppressLint;
 import android.annotation.TargetApi;
 import android.app.Activity;
 import android.app.SearchManager;
@@ skipping 1290 matching lines @@
         return nativeGetCurrentRenderProcessId(mNativeContentViewCore);
     }
 
     /**
      * To be called when the ContentView is hidden.
      */
     public void onHide() {
         assert mWebContents != null;
         hidePopupsAndPreserveSelection();
         mWebContents.onHide();
+        mImeAdapter.resetAndHideKeyboard();

[Changwan Ryu, 2016/09/21 01:22:45]

As we talked offline, I'm still not convinced that we can call this on hiding a
tab. There is no guarantee that either previous tab's view or new tab's view is
active at this point. There is a chance that keyboard hiding may not be
effective. Could it be one of the causes of test flakiness?

     }
 
     private void hidePopupsAndClearSelection() {
         mUnselectAllOnActionModeDismiss = true;
         hidePopups();
     }
 
     @CalledByNative
     private void hidePopupsAndPreserveSelection() {
         mUnselectAllOnActionModeDismiss = false;
@@ skipping 2087 matching lines @@
             String textTrackTextShadow, String textTrackTextSize);
 
     private native void nativeExtractSmartClipData(long nativeContentViewCoreImpl,
             int x, int y, int w, int h);
 
     private native void nativeSetBackgroundOpaque(long nativeContentViewCoreImpl, boolean opaque);
     private native boolean nativeIsTouchDragDropEnabled(long nativeContentViewCoreImpl);
     private native void nativeOnDragEvent(long nativeContentViewCoreImpl, int action, int x, int y,
             int screenX, int screenY, String[] mimeTypes, String content);
 }