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/plugins/clangrefactoring/clangrefactoring.pro

@@ -5,7 +5,13 @@ include(../../shared/clang/clang_installation.pri)
 include(../../shared/clang/clang_defines.pri)
 
 HEADERS += \
-    $$PWD/clangrefactoringplugin.h
+    $$PWD/clangrefactoringplugin.h \
+    qtcreatorsearch.h \
+    qtcreatorsearchhandle.h \
+    qtcreatorclangqueryfindfilter.h
 
 SOURCES += \
-    $$PWD/clangrefactoringplugin.cpp
+    $$PWD/clangrefactoringplugin.cpp \
+    qtcreatorsearch.cpp \
+    qtcreatorsearchhandle.cpp \
+    qtcreatorclangqueryfindfilter.cpp