Adding test case for var keyword

Author: LucianoPAlmeida

lib/Parse/ParseDecl.cpp

@@ -5782,6 +5782,7 @@ Parser::parseDeclEnumCase(ParseDeclOptions Flags,
           return Status;
         }
       }
+      
       if (NameIsKeyword) {
         diagnose(TokLoc, diag::keyword_cant_be_identifier, TokText);
         diagnose(TokLoc, diag::backticks_to_escape)

test/Parse/enum.swift

@@ -560,6 +560,12 @@ enum SR11261 {
   case identifier2
 }
 
+enum SR11261_var {
+  case identifier
+  case var // expected-error {{keyword 'var' cannot be used as an identifier here}} expected-note {{if this name is unavoidable, use backticks to escape it}} {{8-11=`var`}}
+  case identifier2
+}
+
 enum SR11261_1 {
   case a, b, c, func, d // expected-error {{keyword 'func' cannot be used as an identifier here}} expected-note {{if this name is unavoidable, use backticks to escape it}} {{17-21=`func`}}
 }