C#: Add support for the use of synthetic fields in flow summary CSV.

Author: michaelnebel

csharp/ql/lib/semmle/code/csharp/dataflow/internal/FlowSummaryImplSpecific.qll

@@ -136,6 +136,11 @@ SummaryComponent interpretComponentSpecific(string c) {
     c.regexpCapture("Property\\[(.+)\\]", 1) = p.getQualifiedName() and
     result = SummaryComponent::content(any(PropertyContent pc | pc.getProperty() = p))
   )
+  or
+  exists(SyntheticField f |
+    c.regexpCapture("SyntheticField\\[(.+)\\]", 1) = f and
+    result = SummaryComponent::content(any(SyntheticFieldContent sfc | sfc.getField() = f))
+  )
 }
 
 /** Gets the textual representation of the content in the format used for flow summaries. */
@@ -145,6 +150,8 @@ private string getContentSpecificCsv(Content c) {
   exists(Field f | c = TFieldContent(f) and result = "Field[" + f.getQualifiedName() + "]")
   or
   exists(Property p | c = TPropertyContent(p) and result = "Property[" + p.getQualifiedName() + "]")
+  or
+  exists(SyntheticField f | c = TSyntheticFieldContent(f) and result = "SyntheticField[" + f + "]")
 }
 
 /** Gets the textual representation of a summary component in the format used for flow summaries. */