CppTools: ProjectPart now collects warning flags

Will be used by ClangCodeModel, but native model also can use it by
disabling unused variable/parameter warnings when needed.

Change-Id: I184efb3c65e893a2d85a933385cc547b646e6826
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>

src/plugins/cpptools/cppmodelmanagerinterface.cpp

@@ -52,6 +52,16 @@
 using namespace CppTools;
 using namespace ProjectExplorer;
 
+ProjectPart::ProjectPart()
+    : cVersion(C89)
+    , cxxVersion(CXX11)
+    , cxxExtensions(NoExtensions)
+    , qtVersion(UnknownQt)
+    , cWarningFlags(ProjectExplorer::ToolChain::WarningsDefault)
+    , cxxWarningFlags(ProjectExplorer::ToolChain::WarningsDefault)
+{
+}
+
 /**
  * @brief Retrieves info from concrete compiler using it's flags.
  * @param tc Either nullptr or toolchain for project's active target.
@@ -90,6 +100,9 @@ void ProjectPart::evaluateToolchain(const ToolChain *tc,
     if (cxx | ToolChain::OpenMP)
         cxxExtensions |= OpenMP;
 
+    cWarningFlags = tc->warningFlags(cflags);
+    cxxWarningFlags = tc->warningFlags(cxxflags);
+
     QList<HeaderPath> headers = tc->systemHeaderPaths(cxxflags, sysRoot);
     foreach (const HeaderPath &header, headers)
         if (header.kind() == HeaderPath::FrameworkHeaderPath)