[clang] [modules] Move diagnostic about specific mtime/size change into a note from an error. (PR #181963)

[Volodymyr Sapsai via cfe-commits]

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@@ -19,9 +19,10 @@ def err_fe_pch_malformed_block : Error<
     "malformed block record in PCH file: '%0'">, DefaultFatal;
 def err_fe_ast_file_modified : Error<
     "file '%0' has been modified since the "
-    "%select{precompiled header|module file|precompiled file}1 '%2' was built"
-    ": %select{size|mtime|content}3 changed%select{| (was %5, now %6)}4">,
+    "%select{precompiled header|module file|precompiled file}1 '%2' was built">,
     DefaultFatal;
+def note_fe_ast_file_modified : Note<
+    "%select{size|mtime|content}0 changed%select{| from expected %2 to %3}1">;
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vsapsai wrote:

Dropped the parenthesis (feel weird in short statement).

https://github.com/llvm/llvm-project/pull/181963