[clang] [clang-format]: Fix formatting of if statements with BlockIndent (PR #77699)

[Owen Pan via cfe-commits]

================
@@ -768,15 +768,25 @@ void ContinuationIndenter::addTokenOnCurrentLine(LineState &State, bool DryRun,
   // parenthesis by disallowing any further line breaks if there is no line
   // break after the opening parenthesis. Don't break if it doesn't conserve
   // columns.
+  const auto IsOpeningBracket = [&](const FormatToken &Tok) {
+    const auto IsStartOfBracedList = [&]() {
+      return Tok.is(tok::l_brace) && Tok.isNot(BK_Block) &&
+             Style.Cpp11BracedListStyle;
+    };
+    if (Tok.isOneOf(tok::l_paren, TT_TemplateOpener, tok::l_square) ||
+        IsStartOfBracedList()) {
+      if (!Tok.Previous)
+        return true;
+      if (Tok.Previous->isIf())
+        return Style.AlignAfterOpenBracket == FormatStyle::BAS_AlwaysBreak;
+      return !Tok.Previous->isOneOf(TT_CastRParen, tok::kw_for, tok::kw_while,
+                                    tok::kw_switch);
+    }
+    return false;
----------------
owenca wrote:

```suggestion
    if (!Tok.isOneOf(tok::l_paren, TT_TemplateOpener, tok::l_square) &&
        !IsStartOfBracedList()) {
      return false;
    }
    if (!Tok.Previous)
      return true;
    if (Tok.Previous->isIf())
      return Style.AlignAfterOpenBracket == FormatStyle::BAS_AlwaysBreak;
    return !Tok.Previous->isOneOf(TT_CastRParen, tok::kw_for, tok::kw_while,
                                  tok::kw_switch);
```

https://github.com/llvm/llvm-project/pull/77699