Fix CopyBufferSubData.

src/libGLESv2/Buffer.cpp

@@ -48,7 +48,7 @@ void Buffer::bufferSubData(const void *data, GLsizeiptr size, GLintptr offset)
 
 void Buffer::copyBufferSubData(Buffer* source, GLintptr sourceOffset, GLintptr destOffset, GLsizeiptr size)
 {
-    mBuffer->copySubData(source->getImplementation(), size, sourceOffset, destOffset);
+    mBuffer->copySubData(source->getImplementation(), sourceOffset, destOffset, size);
 }
 
 GLvoid *Buffer::mapRange(GLintptr offset, GLsizeiptr length, GLbitfield access)

src/libGLESv2/libGLESv2.cpp

@@ -6589,6 +6589,7 @@ void __stdcall glCopyBufferSubData(GLenum readTarget, GLenum writeTarget, GLintp
             return gl::error(GL_INVALID_OPERATION);
         }
 
+        // Verify that readBuffer and writeBuffer are not currently mapped
         if (readBuffer->isMapped() || writeBuffer->isMapped())
         {
             return gl::error(GL_INVALID_OPERATION);
@@ -6606,8 +6607,6 @@ void __stdcall glCopyBufferSubData(GLenum readTarget, GLenum writeTarget, GLintp
             return gl::error(GL_INVALID_VALUE);
         }
 
-        // TODO: Verify that readBuffer and writeBuffer are not currently mapped (GL_INVALID_OPERATION)
-
         // if size is zero, the copy is a successful no-op
         if (size > 0)
         {

src/libGLESv2/renderer/d3d/d3d9/Buffer9.cpp

@@ -92,6 +92,7 @@ void Buffer9::setSubData(const void* data, size_t size, size_t offset)
 
 void Buffer9::copySubData(BufferImpl* source, GLintptr sourceOffset, GLintptr destOffset, GLsizeiptr size)
 {
+    // Note: this method is currently unreachable
     Buffer9* sourceBuffer = makeBuffer9(source);
     if (sourceBuffer)
     {