GAL: Fix offset problem in multiline text rendering

Commit BZR 6703 introduced a minor horizontal adjustment for stroke
text rendering in GAL, but the Translate() call was done before
calling Save(). So, when this function was called multiple times a
residual offset carried over to each subsequent line.

bzr 6703 = git 67982a4

common/gal/stroke_font.cpp

@@ -255,6 +255,9 @@ void STROKE_FONT::drawSingleLineText( const UTF8& aText )
     VECTOR2D textSize = computeTextLineSize( aText );
     double half_thickness = m_gal->GetLineWidth()/2;
 
+    // Context needs to be saved before any transformations
+    m_gal->Save();
+
     // First adjust: the text X position is corrected by half_thickness
     // because when the text with thickness is draw, its full size is textSize,
     // but the position of lines is half_thickness to textSize - half_thickness
@@ -262,8 +265,6 @@ void STROKE_FONT::drawSingleLineText( const UTF8& aText )
     // to place the text inside the 0 to textSize X area.
     m_gal->Translate( VECTOR2D( half_thickness, 0 ) );
 
-    m_gal->Save();
-
     // Adjust the text position to the given horizontal justification
     switch( m_gal->GetHorizontalJustify() )
     {