Error_Assertion: Remove unused function.

Remove the getAssertionBacktrace() function, which isn't used anywhere.
This function is also a bit misleading, since it doesn't actually return
the backtrace from where the assertion failed.

git-svn-id: https://simplesamlphp.googlecode.com/svn/trunk@1562 44740490-163a-0410-bde0-09ae8108e29a

lib/SimpleSAML/Error/Assertion.php

@@ -34,17 +34,6 @@ class SimpleSAML_Error_Assertion extends SimpleSAML_Error_Error {
 	}
 
 
-	/**
-	 * Retrieve backtrace from where the assert-function was called.
-	 *
-	 * @return array  Array with a backtrace. Each element is a string which identifies a position
-	 *                in the source.
-	 */
-	public function getAssertionBacktrace() {
-		return SimpleSAML_Utilities::buildBacktrace($this, 2);
-	}
-
-
 	/**
 	 * Retrieve the assertion which failed.
 	 *