PEAR: improve realism for tests involving closures

Verified that all closures in test cases are:
* either assigned to a variable
* or used as a function call parameter / callback
* or otherwise "valid"/realistic code

In those cases where this wasn't the case before, the test cases have been adjusted in the most minimal fashion possible.

Author: jrfnl

src/Standards/PEAR/Tests/Functions/FunctionCallSignatureUnitTest.inc

@@ -345,7 +345,7 @@ $x = $var('y',
 $obj->{$x}(1,
   2);
 
-(function ($a, $b) {
+return (function ($a, $b) {
     return function ($c, $d) use ($a, $b) {
         echo $a, $b, $c, $d;
     };
@@ -366,7 +366,7 @@ class Foo
     }
 }
 
-(function ($a, $b) {
+return (function ($a, $b) {
     return function ($c, $d) use ($a, $b) {
         echo $a, $b, $c, $d;
     };

src/Standards/PEAR/Tests/Functions/FunctionCallSignatureUnitTest.inc.fixed

@@ -356,7 +356,7 @@ $obj->{$x}(
     2
 );
 
-(function ($a, $b) {
+return (function ($a, $b) {
     return function ($c, $d) use ($a, $b) {
         echo $a, $b, $c, $d;
     };
@@ -379,7 +379,7 @@ class Foo
     }
 }
 
-(function ($a, $b) {
+return (function ($a, $b) {
     return function ($c, $d) use ($a, $b) {
         echo $a, $b, $c, $d;
     };

src/Standards/PEAR/Tests/Functions/ValidDefaultValueUnitTest.inc

@@ -93,7 +93,7 @@ function foo($baz, Foo $foo = null, $bar = true) {}
 function foo($baz, $bar = true, Foo $foo = null) {}
 
 // Valid closure
-function ($arg1, $arg2='hello') {};
+$closure = function ($arg1, $arg2='hello') {};
 
 // Invalid closure
-function(array $arg2=array(), array $arg1) {}
+$closure = function(array $arg2=array(), array $arg1) {}