Description:
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When I use a variable value as a class name, the file namespace is not recognized. 

Test script:
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<?php
namespace test;
class Test{}
new Test;
$className = '\test\Test'; 
new $className; // this works
$className = 'Test';
new $className; // this should work either, because this file declares the test namespace, but it does not recognize class Test.

Expected result:
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I expect to see no error. 

Actual result:
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Fatal error: Class 'Test' not found in ...