Add clang_getDiagnosticSetFromTU() to libclang.  Fixes <rdar://problem/10553081>.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@146287 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang-c/Index.h b/include/clang-c/Index.h
index dac8b54..65e98ad 100644
--- a/include/clang-c/Index.h
+++ b/include/clang-c/Index.h
@@ -620,6 +620,15 @@
                                                 unsigned Index);
 
 /**
+ * \brief Retrieve the complete set of diagnostics associated with a
+ *        translation unit.
+ *
+ * \param Unit the translation unit to query.
+ */
+CINDEX_LINKAGE CXDiagnosticSet
+  clang_getDiagnosticSetFromTU(CXTranslationUnit Unit);  
+
+/**
  * \brief Destroy a diagnostic.
  */
 CINDEX_LINKAGE void clang_disposeDiagnostic(CXDiagnostic Diagnostic);