bug #274 Adds $this hint support (TheRealDarklord)

This PR was merged into the 4.0-dev branch.

Discussion
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Adds $this hint support

PR for issue FriendsOfPHP/Sami#273

Commits
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8590c01 Add $this as class name alias for hints

Sami/Parser/NodeVisitor.php

@@ -314,7 +314,7 @@ protected function resolveAlias($alias)
         $class = $this->context->getClass();
 
         // special aliases
-        if ('self' === $alias || 'static' === $alias) {
+        if ('self' === $alias || 'static' === $alias || '\$this' === $alias) {
             return $class->getName();
         }