set_content

Sets a new content provider on this.

The clipboard will claim the `GdkDisplay`'s resources and advertise these new contents to other applications.

In the rare case of a failure, this function will return false. The clipboard will then continue reporting its old contents and ignore provider.

If the contents are read by either an external application or the this's read functions, this will select the best format to transfer the contents and then request that format from provider.

Parameters:

this	a `GdkClipboard`
provider	the new contents of this or null to clear the clipboard

Returns:

true if setting the clipboard succeeded