Test that there is no dependency of Image headers on StridedArrayView.

Well. BOOM.

src/Magnum/Test/ImageTest.cpp

@@ -23,15 +23,18 @@
     DEALINGS IN THE SOFTWARE.
 */
 
+/* Included as first to check that we *really* don't need the StridedArrayView
+   header for definition of pixels() */
+#include "Magnum/Image.h"
+
 #include <sstream>
 #include <Corrade/Containers/StridedArrayView.h>
 #include <Corrade/TestSuite/Tester.h>
 #include <Corrade/Utility/DebugStl.h>
 
-#include "Magnum/Image.h"
 #include "Magnum/ImageView.h"
-#include "Magnum/Math/Color.h"
 #include "Magnum/PixelFormat.h"
+#include "Magnum/Math/Color.h"
 
 namespace Magnum { namespace Test { namespace {
 

src/Magnum/Test/ImageViewTest.cpp

@@ -23,14 +23,17 @@
     DEALINGS IN THE SOFTWARE.
 */
 
+/* Included as first to check that we *really* don't need the StridedArrayView
+   header for definition of pixels() */
+#include "Magnum/ImageView.h"
+
 #include <sstream>
 #include <Corrade/Containers/StridedArrayView.h>
 #include <Corrade/TestSuite/Tester.h>
 #include <Corrade/Utility/DebugStl.h>
 
-#include "Magnum/Math/Color.h"
-#include "Magnum/ImageView.h"
 #include "Magnum/PixelFormat.h"
+#include "Magnum/Math/Color.h"
 
 namespace Magnum { namespace Test { namespace {
 

src/Magnum/Trade/Test/ImageDataTest.cpp

@@ -23,15 +23,18 @@
     DEALINGS IN THE SOFTWARE.
 */
 
+/* Included as first to check that we *really* don't need the StridedArrayView
+   header for definition of pixels() */
+#include "Magnum/Trade/ImageData.h"
+
 #include <sstream>
 #include <Corrade/Containers/StridedArrayView.h>
 #include <Corrade/TestSuite/Tester.h>
 #include <Corrade/Utility/DebugStl.h>
 
 #include "Magnum/ImageView.h"
-#include "Magnum/Math/Color.h"
 #include "Magnum/PixelFormat.h"
-#include "Magnum/Trade/ImageData.h"
+#include "Magnum/Math/Color.h"
 
 namespace Magnum { namespace Trade { namespace Test { namespace {