Added tests for static class feature.

Added compile-time check to enforce all methods must be declared static in a static class.
Added compile-time mutual-exclusivity check for static classes marked with abstract or readonly modifiers.
Added compile-time check to preclude static class inheriting from non-static class and vice-versa.
Added compile-time check to preclude static class using a trait with non-static properties or methods.
Fixed ZEND_ACC_IMPLICIT_ABSTRACT_CLASS collision with ZEND_ACC_STATIC.

Author: Bilge

Zend/tests/static_class/inherit_non-static_subclass.phpt

@@ -0,0 +1,11 @@
+--TEST--
+Tests that a non-static class cannot inherit from a static class
+--FILE--
+<?php
+
+static class C {}
+
+class C2 extends C {}
+?>
+--EXPECTF--
+Fatal error: Non-static class C2 cannot extend static class C in %s on line %d

Zend/tests/static_class/inherit_non-static_superclass.phpt

@@ -0,0 +1,11 @@
+--TEST--
+Tests that a static class cannot inherit from a non-static class
+--FILE--
+<?php
+
+class C {}
+
+static class C2 extends C {}
+?>
+--EXPECTF--
+Fatal error: Static class C2 cannot extend non-static class C in %s on line %d

Zend/tests/static_class/inherit_static_class.phpt

@@ -0,0 +1,10 @@
+--TEST--
+Tests that a static class can inherit from another static class
+--FILE--
+<?php
+
+static class C {}
+
+static class C2 extends C {}
+?>
+--EXPECT--

Zend/tests/static_class/inherit_trait.phpt

@@ -0,0 +1,21 @@
+--TEST--
+Tests that a static class can inherit static members from a trait
+--FILE--
+<?php
+
+trait T {
+    static $P = 'OK';
+
+    static function F() {
+        echo self::$P;
+    }
+}
+
+static class C {
+    use T;
+}
+
+C::F();
+?>
+--EXPECT--
+OK

Zend/tests/static_class/inherit_trait_instance_method.phpt

@@ -0,0 +1,15 @@
+--TEST--
+Tests that a static class cannot inherit an instance method from a trait
+--FILE--
+<?php
+
+trait T {
+    function F() {}
+}
+
+static class C {
+    use T;
+}
+?>
+--EXPECTF--
+Fatal error: Static class C cannot use trait with a non-static method T::F in %s on line %d

Zend/tests/static_class/inherit_trait_instance_property.phpt

@@ -0,0 +1,15 @@
+--TEST--
+Tests that a static class cannot inherit an instance property from a trait
+--FILE--
+<?php
+
+trait T {
+    var $V;
+}
+
+static class C {
+    use T;
+}
+?>
+--EXPECTF--
+Fatal error: Static class C cannot use trait with a non-static property T::$V in %s on line %d

Zend/tests/static_class/new_static_class.phpt

@@ -0,0 +1,12 @@
+--TEST--
+Tests that a static class cannot be instantiated
+--FILE--
+<?php
+
+static class C {}
+
+new C;
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Cannot instantiate static class C in %s:%d
+Stack trace:%a

Zend/tests/static_class/new_static_class_via_reflection.phpt

@@ -0,0 +1,12 @@
+--TEST--
+Tests that a static class cannot be instantiated via reflection
+--FILE--
+<?php
+
+static class C {}
+
+new ReflectionClass('C')->newInstance();
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Cannot instantiate static class C in %s:%d
+Stack trace:%a

Zend/tests/static_class/static_abstract_class.phpt

@@ -0,0 +1,9 @@
+--TEST--
+Tests that a static class cannot be marked abstract
+--FILE--
+<?php
+
+abstract static class C {}
+?>
+--EXPECTF--
+Fatal error: Cannot use the static modifier on an abstract class in %s on line %d

Zend/tests/static_class/static_anonymous_class.phpt

@@ -0,0 +1,9 @@
+--TEST--
+Tests that an anonymous class cannot be marked static
+--FILE--
+<?php
+
+new static class C {}
+?>
+--EXPECTF--
+Fatal error: Cannot use the static modifier on an anonymous class in %s on line %d