Minor bug fixes and cleanup

- Removed unused variables
- Fixed member initialization order in a few classes
- Fixed Surface::setSwapBehavior()
- Removed unused mPixelPackingStateDirty members
- Fixed initialization of "size" member in LinkedVarying class
- Fixed constness of a string
- Removed unused static functions
- Added parenthesis to fix && / || order ambiguity

Change-Id: Ia9ad8eaca335c60871fdc58037e441aa2010a641
Reviewed-on: https://swiftshader-review.googlesource.com/4301
Tested-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Nicolas Capens <capn@google.com>

src/Renderer/Matrix.cpp

diff --git a/src/Renderer/Matrix.cpp b/src/Renderer/Matrix.cpp
index 68aa549..3c3567a 100644
--- a/src/Renderer/Matrix.cpp
+++ b/src/Renderer/Matrix.cpp
@@ -343,9 +343,9 @@
 		float sxsy = sx * sy;
 		float sxcy = sx * cy;
 
-		return Matrix(cy * cz - sy * sx * sz, -cy * sz - sy * sx * cz, -sy * cx,
-		              cx * sz,                 cx * cz,                -sx,
-		              sy * cz + cy * sx * sz, -sy * sz + cy * sx * cz,  cy * cx);
+		return Matrix(cy * cz - sxsy * sz, -cy * sz - sxsy * cz, -sy * cx,
+		              cx * sz,              cx * cz,             -sx,
+		              sy * cz + sxcy * sz, -sy * sz + sxcy * cz,  cy * cx);
 	}
 
 	Matrix Matrix::eulerRotate(float x, float y, float z)