Fix C++11 strict string literal const correctness.

String literals are const in C++11, and should only be assigned to
const pointers.

Bug swiftshader:33

Change-Id: Iefe0a1c06d58dffb69d7fbe199a2f0aa8bf3bcb1
Reviewed-on: https://swiftshader-review.googlesource.com/8990
Tested-by: Nicolas Capens <capn@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>

src/OpenGL/libGL/Shader.cpp

diff --git a/src/OpenGL/libGL/Shader.cpp b/src/OpenGL/libGL/Shader.cpp
index 14983bd..3a6b2cd 100644
--- a/src/OpenGL/libGL/Shader.cpp
+++ b/src/OpenGL/libGL/Shader.cpp
@@ -197,7 +197,7 @@
 	TranslatorASM *compiler = createCompiler(getType());
 
 	// Ensure we don't pass a nullptr source to the compiler
-	char *source = "\0";
+	const char *source = "\0";
 	if(mSource)
 	{
 		source = mSource;

tests/OGLSimpleCube/OGLSimpleCube.cpp

diff --git a/tests/OGLSimpleCube/OGLSimpleCube.cpp b/tests/OGLSimpleCube/OGLSimpleCube.cpp
index afa63f1..bfcf569 100644
--- a/tests/OGLSimpleCube/OGLSimpleCube.cpp
+++ b/tests/OGLSimpleCube/OGLSimpleCube.cpp
@@ -37,7 +37,7 @@
 LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam);
 
 const char *className = "OpenGL";
-char *windowName = "OpenGL Cube";
+const char *windowName = "OpenGL Cube";
 int winX = 0, winY = 0;
 int winWidth = 300, winHeight = 300;
 float angle = 0.1f;