Support dragging texts out of webview/Chrome.

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

Index: content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java b/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
index a1c24280c5b732b2a1b95590c535631f9fb6ad3a..a020be2d61a46fb6e6e8b64669c6f82139adc815 100644
--- a/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
+++ b/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
@@ -47,6 +47,7 @@ import android.view.inputmethod.EditorInfo;
 import android.view.inputmethod.InputConnection;
 import android.view.inputmethod.InputMethodManager;
 import android.widget.FrameLayout;
+import android.widget.ImageView;
 
 import org.chromium.base.ApiCompatibilityUtils;
 import org.chromium.base.CommandLine;
@@ -155,6 +156,8 @@ public class ContentViewCore implements AccessibilityStateChangeListener, Screen
      * that clients can safely hold to instances of this class.
      */
     private static class ContentViewAndroidDelegate implements ViewAndroidDelegate {
+        // TODO(hush): use View#DRAG_FLAG_GLOBAL when Chromium starts to build with API 24.
+        private static final int DRAG_FLAG_GLOBAL = 1 << 8;
         /**
          * Represents the position of an anchor view.
          */
@@ -297,6 +300,21 @@ public class ContentViewCore implements AccessibilityStateChangeListener, Screen
                 }
             }
         }
+
+        public void startDragAndDrop(String text, Bitmap shadowImage) {
+            ClipData data = ClipData.newPlainText(null, text);
+
+            ViewGroup containerView = mCurrentContainerView.get();
+            if (containerView == null) return;
+
+            ImageView imageView = new ImageView(containerView.getContext());
+            imageView.setImageBitmap(shadowImage);
+            imageView.layout(0, 0, shadowImage.getWidth(), shadowImage.getHeight());
+
+            // TODO(hush): use View#startDragAndDrop when Chromium starts to build with API 24.
+            containerView.startDrag(

[Theresa, 2016/07/13 22:55:42]

This method is deprecated in API 24, so there will likely be lint warnings for
anyone building against the new API. Right now lint warnings don't do anything
but eventually we'd like to treat warnings as errors. Will you please suppress
the warning?

[hush (inactive), 2016/07/14 18:42:09]

Yes, done.

+                    data, new View.DragShadowBuilder(imageView), null, DRAG_FLAG_GLOBAL);
+        }
     }
 
     /**
@@ -1466,6 +1484,7 @@ public class ContentViewCore implements AccessibilityStateChangeListener, Screen
         hidePopups();
     }
 
+    @CalledByNative
     private void hidePopupsAndPreserveSelection() {
         mUnselectAllOnActionModeDismiss = false;
         hidePopups();