[clang-format] Stop fixing indentation on namespace closing brace (#122234)

Fixes #119790.

Author: owenca

clang/lib/Format/UnwrappedLineFormatter.cpp

@@ -1460,7 +1460,7 @@ unsigned UnwrappedLineFormatter::format(
     bool ContinueFormatting =
         TheLine.Level > RangeMinLevel ||
         (TheLine.Level == RangeMinLevel && !PreviousRBrace &&
-         !TheLine.startsWith(tok::r_brace));
+         !TheLine.startsWith(TT_NamespaceRBrace));
 
     bool FixIndentation = (FixBadIndentation || ContinueFormatting) &&
                           Indent != TheLine.First->OriginalColumn;

clang/unittests/Format/FormatTestSelective.cpp

@@ -388,6 +388,17 @@ TEST_F(FormatTestSelective, WrongIndent) {
                    "  int j;\n" // Format here.
                    "}",
                    24, 0));
+  EXPECT_EQ("namespace {\n"
+            "class C {\n"
+            "  int i;\n"
+            "};\n"
+            "} // namespace",
+            format("namespace {\n" // Format here.
+                   "  class C {\n"
+                   "    int i;\n"
+                   "  };\n"
+                   "}",
+                   1, 0));
 }
 
 TEST_F(FormatTestSelective, AlwaysFormatsEntireMacroDefinitions) {