Microsoft.CodeAnalysis.FlowAnalysis.DataFlow.DataFlowOperationVisitor<TAnalysisData, TAnalysisContext, TAnalysisResult, TAbstractAnalysisValue>.ComputeValueForCompoundAssignment(Microsoft.CodeAnalysis.Operations.ICompoundAssignmentOperation, TAbstractAnalysisValue, TAbstractAnalysisValue, Microsoft.CodeAnalysis.ITypeSymbol, Microsoft.CodeAnalysis.ITypeSymbol)