Add support for PartDesign:Body colors

When the tip of a PartDesign:Body is colorized, the colors are stored
on tip level. But when the shape of the whole body is changed the information
is stored on body level. To account for this we check if the tip has more
than one DiffuseColor set. When not, we use the shape color of the body.

src/Mod/Arch/ArchFence.py

@@ -317,6 +317,18 @@ def applyColors(self, obj):
 
     def normalizeColors(self, obj, numberOfFaces):
         colors = obj.ViewObject.DiffuseColor
+
+        if obj.TypeId == 'PartDesign::Body':
+            # When colorizing a PartDesign Body we have two options
+            # 1. The whole body got a shape color, that means the tip has only a single diffuse color set
+            #   so we use the shape color of the body
+            # 2. "Set colors" was called on the tip and the individual faces where colorized.
+            #   We use the diffuseColors of the tip in that case
+            tipColors = obj.Tip.ViewObject.DiffuseColor
+
+            if len(tipColors) > 1:
+                colors = tipColors
+
         numberOfColors = len(colors)
 
         if numberOfColors == 1: