d3dx9_36: Implement D3DXCreateMesh and initial ID3DXMesh methods.

dlls/d3dx9_36/d3dx9_36_private.h

@@ -93,6 +93,24 @@ typedef struct ID3DXMatrixStackImpl
   D3DXMATRIX *stack;
 } ID3DXMatrixStackImpl;
 
+/* ID3DXMesh */
+typedef struct ID3DXMeshImpl
+{
+    /* IUnknown fields */
+    const ID3DXMeshVtbl *lpVtbl;
+    LONG ref;
+
+    /* ID3DXMesh fields */
+    DWORD numfaces;
+    DWORD numvertices;
+    DWORD options;
+    DWORD fvf;
+    IDirect3DDevice9 *device;
+    IDirect3DVertexDeclaration9 *vertex_declaration;
+    IDirect3DVertexBuffer9 *vertex_buffer;
+    IDirect3DIndexBuffer9 *index_buffer;
+} ID3DXMeshImpl;
+
 /*ID3DXSprite */
 typedef struct _SPRITE {
     LPDIRECT3DTEXTURE9 texture;