element.py: Remove redundant context from Plugin.warn() invokation
When calling `self.warn()` there is no need to print the element name or
print "WARNING", this context is implied by calling `Plugin.warn()` already.
diff --git a/src/buildstream/element.py b/src/buildstream/element.py
index 8f47a5b..7fbadc2 100644
--- a/src/buildstream/element.py
+++ b/src/buildstream/element.py
@@ -1472,7 +1472,7 @@
import_dir = self.__artifact.get_buildtree()
if not import_dir:
detail = "Element type either does not expect a buildtree or it was explictily cached without one."
- self.warn("WARNING: {} Artifact contains an empty buildtree".format(self.name), detail=detail)
+ self.warn("Artifact contains an empty buildtree", detail=detail)
# No cached buildtree, stage source from source cache
else:
