Make -Wformat fix-its preserve original conversion specifiers.

This commit makes PrintfSpecifier::fixType() and ScanfSpecifier::fixType()
only fix a conversion specification enough that Clang wouldn't warn about it,
as opposed to always changing it to use the "canonical" conversion specifier.
(PR11975)

This preserves the user's choice of conversion specifier in cases like:

printf("%a", (long double)1);
where we previously suggested "%Lf", we now suggest "%La"

printf("%x", (long)1);
where we previously suggested "%ld", we now suggest "%lx".

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@150578 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp
index 3393cf7..1d75ef6 100644
--- a/lib/Sema/SemaChecking.cpp
+++ b/lib/Sema/SemaChecking.cpp
@@ -2181,7 +2181,8 @@
 
     // We may be able to offer a FixItHint if it is a supported type.
     PrintfSpecifier fixedFS = FS;
-    bool success = fixedFS.fixType(Ex->getType(), S.getLangOptions());
+    bool success = fixedFS.fixType(Ex->getType(), S.getLangOptions(),
+                                   S.Context, IsObjCLiteral);
 
     if (success) {
       // Get the fix string from the fixed format specifier
@@ -2340,7 +2341,8 @@
   const analyze_scanf::ScanfArgTypeResult &ATR = FS.getArgType(S.Context);
   if (ATR.isValid() && !ATR.matchesType(S.Context, Ex->getType())) {
     ScanfSpecifier fixedFS = FS;
-    bool success = fixedFS.fixType(Ex->getType(), S.getLangOptions());
+    bool success = fixedFS.fixType(Ex->getType(), S.getLangOptions(),
+                                   S.Context);
 
     if (success) {
       // Get the fix string from the fixed format specifier.