tests: Use one shared xzalloc implementation

Since this is an inlined function, move it to a common header file.

Signed-off-by: Bryce Harrington <bryce@osg.samsung.com>
Reviewed-by: Marek Chalupa <mchqwerty@gmail.com>

tests/presentation-test.c

@@ -31,17 +31,6 @@
 #include "weston-test-client-helper.h"
 #include "presentation_timing-client-protocol.h"
 
-static inline void *
-xzalloc(size_t size)
-{
-	void *p;
-
-	p = calloc(1, size);
-	assert(p);
-
-	return p;
-}
-
 static struct presentation *
 get_presentation(struct client *client)
 {

tests/weston-test-client-helper.c

@@ -32,17 +32,6 @@
 #include "../shared/os-compatibility.h"
 #include "weston-test-client-helper.h"
 
-static inline void *
-xzalloc(size_t size)
-{
-	void *p;
-
-	p = calloc(1, size);
-	assert(p);
-
-	return p;
-}
-
 int
 surface_contains(struct surface *surface, int x, int y)
 {

tests/weston-test-client-helper.h

@@ -101,6 +101,17 @@ struct surface {
 	void *data;
 };
 
+static inline void *
+xzalloc(size_t size)
+{
+        void *p;
+
+        p = calloc(1, size);
+        assert(p);
+
+        return p;
+}
+
 struct client *
 client_create(int x, int y, int width, int height);