[clang-format] Indent Verilog case statements with comments (#71353)

If a line contains a comment outside of (fake) parentheses, the part
following it is indented according to `CurrentState.Indent`. A Verilog
case label and the statement that follows are broken with
mustBreakBefore. So the part that follows the case label needs some
special handling. Previously, that variable was left out. So the
indentation was wrong when there was a comment.

old:

```Verilog
case (data)
  16'd0:
    result = //
        10'b0111111111;
endcase
case (data)
  16'd0:
    //

  //
  result = //
  10'b0111111111;
endcase
```

new:

```Verilog
case (data)
  16'd0:
    result = //
        10'b0111111111;
endcase
case (data)
  16'd0:
    //

    //
    result = //
        10'b0111111111;
endcase
```

clang/lib/Format/ContinuationIndenter.cpp

@@ -1208,8 +1208,10 @@ unsigned ContinuationIndenter::getNewLineColumn(const LineState &State) {
 
   // Indentation of the statement following a Verilog case label is taken care
   // of in moveStateToNextToken.
-  if (Style.isVerilog() && Keywords.isVerilogEndOfLabel(Previous))
+  if (Style.isVerilog() && PreviousNonComment &&
+      Keywords.isVerilogEndOfLabel(*PreviousNonComment)) {
     return State.FirstIndent;
+  }
 
   if (Style.BreakBeforeBraces == FormatStyle::BS_Whitesmiths &&
       State.Line->First->is(tok::kw_enum)) {
@@ -1612,6 +1614,7 @@ unsigned ContinuationIndenter::moveStateToNextToken(LineState &State,
       State.NextToken->MustBreakBefore &&
       Keywords.isVerilogEndOfLabel(Current)) {
     State.FirstIndent += Style.IndentWidth;
+    CurrentState.Indent = State.FirstIndent;
   }
 
   unsigned Penalty =

clang/unittests/Format/FormatTestVerilog.cpp

@@ -344,6 +344,20 @@ TEST_F(FormatTestVerilog, Case) {
                "        longfunction( //\n"
                "            arg);\n"
                "endcase");
+  verifyFormat("case (data)\n"
+               "  16'd0:\n"
+               "    //\n"
+               "    result = //\n"
+               "        10'b0111111111;\n"
+               "endcase");
+  verifyFormat("case (data)\n"
+               "  16'd0:\n"
+               "    //\n"
+               "\n"
+               "    //\n"
+               "    result = //\n"
+               "        10'b0111111111;\n"
+               "endcase");
   Style = getDefaultStyle();
   Style.ContinuationIndentWidth = 1;
   verifyFormat("case (data)\n"