Support dragging texts into Android WebView.

content/browser/android/content_view_core_impl.h

Index: content/browser/android/content_view_core_impl.h
diff --git a/content/browser/android/content_view_core_impl.h b/content/browser/android/content_view_core_impl.h
index aab7ecafbd0a15b6bac63a572ac2387791c065a1..a8e07303f2d7a27459a8e309f790f30a6eed52c3 100644
--- a/content/browser/android/content_view_core_impl.h
+++ b/content/browser/android/content_view_core_impl.h
@@ -278,6 +278,27 @@ class ContentViewCoreImpl : public ContentViewCore,
   void SetBackgroundOpaque(JNIEnv* env,
                            const base::android::JavaParamRef<jobject>& jobj,
                            jboolean opaque);
+  void OnDragEntered(JNIEnv* env,

[Ted C, 2016/02/25 18:38:53]

again to the api comment, onTouchEvent has a single nativeOnTouchEvent.  I'm
wondering why we need to differ here.

They even pass the java touch event down and things are extracted as needed from
native.

That might be overkill as OnPerformDrop is the only thing that needs anything
else at this point.  We could pass null in other other cases.

Although as soon as we start doing images or anything more fancy, then I would
want to make sure we don't have to pollute the CVC with that logic.

[hush (inactive), 2016/02/27 01:46:13]

Yes, I will replace this bunch with OnDragEvent.

+                     const base::android::JavaParamRef<jobject>& jobj,
+                     int x,
+                     int y,
+                     int screen_x,
+                     int screen_y);
+  void OnDragUpdated(JNIEnv* env,
+                     const base::android::JavaParamRef<jobject>& jobj,
+                     int x,
+                     int y,
+                     int screen_x,
+                     int screen_y);
+  void OnPerformDrop(JNIEnv* env,
+                     const base::android::JavaParamRef<jobject>& jobj,
+                     int x,
+                     int y,
+                     int screen_x,
+                     int screen_y,
+                     const base::android::JavaParamRef<jstring>& content);
+  void OnDragExited(JNIEnv* env,
+                    const base::android::JavaParamRef<jobject>& jobj);
 
   jint GetCurrentRenderProcessId(
       JNIEnv* env,