Support dragging texts into Android WebView.

content/browser/android/content_view_core_impl.h

 // 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.
 
 #ifndef CONTENT_BROWSER_ANDROID_CONTENT_VIEW_CORE_IMPL_H_
 #define CONTENT_BROWSER_ANDROID_CONTENT_VIEW_CORE_IMPL_H_
 
 #include <stdint.h>
 
 #include <vector>
@@ skipping 260 matching lines @@
   void ExtractSmartClipData(JNIEnv* env,
                             const base::android::JavaParamRef<jobject>& obj,
                             jint x,
                             jint y,
                             jint width,
                             jint height);
 
   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,
       const base::android::JavaParamRef<jobject>& obj);
 
   // --------------------------------------------------------------------------
   // Public methods that call to Java via JNI
   // --------------------------------------------------------------------------
 
   void OnSmartClipDataExtracted(const base::string16& text,
@@ skipping 175 matching lines @@
   scoped_refptr<GinJavaBridgeDispatcherHost> java_bridge_dispatcher_host_;
 
   DISALLOW_COPY_AND_ASSIGN(ContentViewCoreImpl);
 };
 
 bool RegisterContentViewCore(JNIEnv* env);
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_ANDROID_CONTENT_VIEW_CORE_IMPL_H_