ExpressionTransformer #994: remove forOuterCompanion because its logic was broken

limiting to very simple cases of looking at the qualified primary was too simplistic
ExpressionTransformer #994: make sure outer is fully qualified
ExpressionTransformer/Invocation #994/#1023: fixes for accessing interface instances or their $impl class
Invocation: removed dead code
Updated expected .src for #994/#1023
Test for #994: outer[index++] in List