DevTools: move DevToolsAgent/Client into content.

BUG=84078
TEST=

Review URL: http://codereview.chromium.org/7461019

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@93596 0039d316-1c4b-4281-b951-d872f2087c98
void RenderView::OnDragTargetDragEnter(const WebDropData& drop_data,
                                       const gfx::Point& client_point,
                                       const gfx::Point& screen_point,
                                       WebDragOperationsMask ops) {
  WebDragOperation operation = webview()->dragTargetDragEnter(
      drop_data.ToDragData(),
      client_point,
      screen_point,
      ops);

  Send(new DragHostMsg_UpdateDragCursor(routing_id_, operation));
}

void RenderView::OnDragTargetDragEnter(const WebDropData& drop_data,
                                       const gfx::Point& client_point,
                                       const gfx::Point& screen_point,
                                       WebDragOperationsMask ops) {
  WebDragOperation operation = webview()->dragTargetDragEnter(
      drop_data.ToDragData(),
      client_point,
      screen_point,
      ops);

  Send(new DragHostMsg_UpdateDragCursor(routing_id_, operation));
}
