Support dragging texts into Android WebView.

content/browser/renderer_host/render_view_host_impl.cc

Index: content/browser/renderer_host/render_view_host_impl.cc
diff --git a/content/browser/renderer_host/render_view_host_impl.cc b/content/browser/renderer_host/render_view_host_impl.cc
index 5aa3313f278c865aab9af9280ba91a1ab0569b27..b66f8226c0f8a361b8f3ae89c8d90ddf2fc1a6dd 100644
--- a/content/browser/renderer_host/render_view_host_impl.cc
+++ b/content/browser/renderer_host/render_view_host_impl.cc
@@ -713,6 +713,19 @@ void RenderViewHostImpl::DragTargetDrop(
                               key_modifiers));
 }
 
+#if defined(OS_ANDROID)

[aelias_OOO_until_Jul13, 2016/03/01 19:57:32]

Could you remove all "#if defined(OS_ANDROID)" from this patch and also from
https://codereview.chromium.org/1723763002 ?  Just because a codepath happens to
currently be run on Android is not a sufficient reason to have them in my mind. 
They make a lot of things annoying: testing, trybots, code sharing, etc.

[hush (inactive), 2016/03/01 23:54:19]

I merged the new IPC into the existing IPC

+void RenderViewHostImpl::DragTargetDropWithData(const DropData& drop_data,
+                                                const gfx::Point& client_pt,
+                                                const gfx::Point& screen_pt,
+                                                int key_modifiers) {
+  // TODO(hush): filter the drop_data when we start to support dragging files.
+  const gfx::Point client_pt_in_viewport = ConvertDIPToViewport(client_pt);
+  Send(new DragMsg_TargetDropWithData(GetRoutingID(), drop_data,
+                                      client_pt_in_viewport, screen_pt,
+                                      key_modifiers));
+}
+#endif
+
 void RenderViewHostImpl::DragSourceEndedAt(
     int client_x, int client_y, int screen_x, int screen_y,
     WebDragOperation operation) {