drawinglayer: add transparency support to BackgroundColorPrimitive2D

Impress has tools Color that is wrapped in this primitive, then later
drawinglayer::processor2d::VclPixelProcessor2D::processBasePrimitive2D()
converts it back to tools Color. Problem is that the primitive uses basegfx
BColor, so the alpha channel is lost.

Add member and API to survive this roundtrip.

Change-Id: I940e60f6e352022306abac3223636d19dd859355
(cherry picked from commit 9824134ab3c19aa0a00943c65a0e09c36ef23899)

1 files changed, 4 insertions, 2 deletions

diff --git a/drawinglayer/source/primitive2d/backgroundcolorprimitive2d.cxx b/drawinglayer/source/primitive2d/backgroundcolorprimitive2d.cxx
index 3441483a9ac4..ea10d205e2d8 100644
--- a/drawinglayer/source/primitive2d/backgroundcolorprimitive2d.cxx
+++ b/drawinglayer/source/primitive2d/backgroundcolorprimitive2d.cxx
@@ -50,9 +50,11 @@ namespace drawinglayer
         }
 
         BackgroundColorPrimitive2D::BackgroundColorPrimitive2D(
-            const basegfx::BColor& rBColor)
+            const basegfx::BColor& rBColor,
+            double fTransparency)
         :   BufferedDecompositionPrimitive2D(),
             maBColor(rBColor),
+            mfTransparency(fTransparency),
             maLastViewport()
         {
         }
@@ -63,7 +65,7 @@ namespace drawinglayer
             {
                 const BackgroundColorPrimitive2D& rCompare = static_cast<const BackgroundColorPrimitive2D&>(rPrimitive);
 
-                return (getBColor() == rCompare.getBColor());
+                return (getBColor() == rCompare.getBColor() && getTransparency() == rCompare.getTransparency());
             }
 
             return false;