[BLUEJ-1281] Show source link in Javadoc should also position caret

When you view the Documentation view in the editor, there is a "show source" link that we add to enable jumping back to that location in the source code. It scrolls to the given method but then it can take a moment to find that method on screen. It would be better if we also positioned the caret in the source code at the method name (or selected the method name) at the same time.

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Issue metadata

• Issue type: Bug
• Priority: Medium