clang-format: Improve understanding of combined typedef+record declarations

Fixes an issue where struct A { int X; }; would be broken onto multiple
lines, but typedef struct A { int X; } A2; was collapsed onto a single
line.

Patch by Jacob Bandes-Storch. Thank you.

llvm-svn: 305667
diff --git a/clang/lib/Format/UnwrappedLineFormatter.cpp b/clang/lib/Format/UnwrappedLineFormatter.cpp
index 7f64465..63a0b7d 100644
--- a/clang/lib/Format/UnwrappedLineFormatter.cpp
+++ b/clang/lib/Format/UnwrappedLineFormatter.cpp
@@ -434,8 +434,11 @@
     } else if (Limit != 0 && !Line.startsWith(tok::kw_namespace) &&
                !startsExternCBlock(Line)) {
       // We don't merge short records.
-      if (Line.First->isOneOf(tok::kw_class, tok::kw_union, tok::kw_struct,
-                              Keywords.kw_interface))
+      FormatToken *RecordTok =
+          Line.First->is(tok::kw_typedef) ? Line.First->Next : Line.First;
+      if (RecordTok &&
+          RecordTok->isOneOf(tok::kw_class, tok::kw_union, tok::kw_struct,
+                             Keywords.kw_interface))
         return 0;
 
       // Check that we still have three lines and they fit into the limit.