Clang: Add clang query

Clang query is mechanism to use AST matcher to search for code. Think
about regular expression but in the context of AST. So you get a semantic
search tool for C++.

Change-Id: I72e882c5b53a0c52f352a3664847c4c3e4f6fc2e
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

src/libs/clangbackendipc/clangbackendipc_global.h

@@ -29,6 +29,10 @@
 
 #include <QtCore/qglobal.h>
 
+#ifdef UNIT_TESTS
+#include <gtest/gtest.h>
+#endif
+
 #if defined(CLANGBACKENDIPC_BUILD_LIB)
 #  define CMBIPC_EXPORT Q_DECL_EXPORT
 #elif defined(CLANGBACKENDIPC_BUILD_STATIC_LIB)
@@ -41,6 +45,12 @@
 # define CLANGBACKENDPROCESSPATH ""
 #endif
 
+namespace Utils {
+template<uint Size>
+class BasicSmallString;
+using SmallString = BasicSmallString<31>;
+}
+
 namespace ClangBackEnd {
 
 enum class DiagnosticSeverity : quint32 // one to one mapping of the clang enum numbers
@@ -109,7 +119,10 @@ enum class MessageType : quint8 {
     ProjectPartsDoNotExistMessage,
 
     SourceLocationsForRenamingMessage,
-    RequestSourceLocationsForRenamingMessage
+    RequestSourceLocationsForRenamingMessage,
+
+    RequestSourceRangesAndDiagnosticsForQueryMessage,
+    SourceRangesAndDiagnosticsForQueryMessage
 };
 
 template<MessageType messageEnumeration>