CodeCoverage: Apply C# filter only to .cs files

src/AddIns/Analysis/CodeCoverage/Project/Src/CodeCoverageMethodElement.cs

@@ -58,6 +58,7 @@ namespace ICSharpCode.CodeCoverage
 
 		public string FileID { get; private set; }
 		public string FileName { get; private set; }
+		public string FileNameExt { get; private set; }
 		public bool IsVisited { get; private set; }
 		public int CyclomaticComplexity { get; private set; }
 		public decimal SequenceCoverage { get; private set; }
@@ -86,9 +87,14 @@ namespace ICSharpCode.CodeCoverage
 
 			this.FileID = GetFileRef();
 			this.FileName = String.Empty;
+			this.FileNameExt = String.Empty;
 			if (!String.IsNullOrEmpty(this.FileID)) {
 				if (results != null) {
 					this.FileName = results.GetFileName(this.FileID);
+					try {
+						this.FileNameExt = Path.GetExtension(this.FileName);
+					}
+					catch {}
 					if (cacheFileName != this.FileName) {
 						cacheFileName = this.FileName;
 						cacheDocument = GetSource (cacheFileName);
@@ -303,6 +309,8 @@ namespace ICSharpCode.CodeCoverage
 						continue; // skip
 					}
 
+					if (this.FileNameExt == ".cs") {
+						// 0) Only for C#
 						// 1) Generated "in" code for IEnumerables contains hidden "try/catch/finally" branches that
 						// one do not want or cannot cover by test-case because is handled earlier at same method.
 						// ie: NullReferenceException in foreach loop is pre-handled at method entry, ie. by Contract.Require(items!=null)
@@ -321,6 +329,7 @@ namespace ICSharpCode.CodeCoverage
 							sp.BranchCoverage = true;
 							continue; // skip
 						}
+					}
 
 					totalBranchCount += sp.BranchExitsCount;
 					totalBranchVisit += sp.BranchExitsVisit;