Java Semantics Proposal Computer stopping non-blocking Completion

[danthe1st]

Upon installing pde-tools, it is no longer possible to use non-blocking completion for Content-Assist because the Java Semantics Proposal Computer requires the UI thread.

Steps to reproduce:

• Install PDE-Tools
• Select Java>Editor>Content Assist>Advanced
• Check Enable non-blocking completion (does not affect open editors)
• Observe that the option is ignored with the notice

This setting is ignored because the following contributions require UI thread:
* Java Semantics Proposal Computer

This also effects Eclipse if the Java Semantics Proposal Computer is disabled in the Content Assist setting.

I think adding requiresUIThread="false" to

pde-tools/net.jeeeyul.pdetools/plugin.xml

Lines 1044 to 1052 in 342ea53

	<javaCompletionProposalComputer
	activate="false"
	categoryId="net.jeeeyul.pdetoos.java.proposal"
	class="net.jeeeyul.pdetools.jdt.SematicsProposalComputer"
	needsSortingAfterFiltering="false">
	<partition
	type="__dftl_partition_content_type">
	</partition>
	</javaCompletionProposalComputer>

to it as done here could fix it but it might have side effects.