Revert "Draw frame outline at the outer edge, not a pixel further inside"

This reverts commit 7e678c344b and the followup.

   A       B
+-----+ +-----+   C
|     | |XXXXX| +---+
| XXX | |X   X| |XXX|
| XCX | |X C X| |XCX|
| XXX | |X   X| |XXX|
|     | |XXXXX| +---+
+-----+ +-----+

Initially it was A, the referenced commit changed it to be B instead, which
created a 1px gap between frame and content, and the followup avoids that gap
by adjusting the frame width, resulting in C.

Although it's consistent, it leads to a worse apperance in places where the 1px
margin between frame and rect was expected.

kstyle/breezehelper.cpp

@@ -520,7 +520,7 @@ namespace Breeze
 
         painter->setRenderHint( QPainter::Antialiasing );
 
-        QRectF frameRect( rect );
+        QRectF frameRect( rect.adjusted( 1, 1, -1, -1 ) );
         qreal radius( frameRadius( PenWidth::NoPen, -1 ) );
 
         // set pen

kstyle/breezemetrics.h

@@ -35,7 +35,7 @@ namespace Breeze
     struct Metrics
     {
         // frames
-        static constexpr int Frame_FrameWidth = 1;
+        static constexpr int Frame_FrameWidth = 2;
         static constexpr int Frame_FrameRadius = 3;
 
         // layout