QSymbianVGFontGlyphCache implementation is not unscoped if QVG_NO_DRAW_GLYPHS is defined

When compiling Qt for Symbian the qvg.h has the definition of class QSymbianVGFontGlyphCache inside #ifndef QVG_NO_DRAW_GLYPHS. However the implementation in qvg_symbian.cpp does not have the #ifndef around the class implementation. This causes the compilation to fail, because armcc cannot find the class declaration.