Clang: Support MSVC style of compiler flags

Clang has MSVC compatible mode which works with MSVC style command line
flags.

When possible use the same flags (-I, -D, -U, etc.) and in other cases
either replace by MSVC analog (for example use /FI instead of -include)
or pass the argument with '/clang:' prefix (requires
https://reviews.llvm.org/D53457).

Change-Id: I95f33bed5dc8d9493895ed8d4359cdd70fc774b8
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@qt.io>

src/plugins/cpptools/cppprojectfile.cpp

@@ -118,6 +118,42 @@ bool ProjectFile::isSource() const
     return isSource(kind);
 }
 
+bool ProjectFile::isC(ProjectFile::Kind kind)
+{
+    switch (kind) {
+    case ProjectFile::CHeader:
+    case ProjectFile::CSource:
+    case ProjectFile::ObjCHeader:
+    case ProjectFile::ObjCSource:
+        return true;
+    default:
+        return false;
+    }
+}
+
+bool ProjectFile::isCxx(ProjectFile::Kind kind)
+{
+    switch (kind) {
+    case ProjectFile::CXXHeader:
+    case ProjectFile::CXXSource:
+    case ProjectFile::ObjCXXHeader:
+    case ProjectFile::ObjCXXSource:
+        return true;
+    default:
+        return false;
+    }
+}
+
+bool ProjectFile::isC() const
+{
+    return isC(kind);
+}
+
+bool ProjectFile::isCxx() const
+{
+    return isCxx(kind);
+}
+
 #define RETURN_TEXT_FOR_CASE(enumValue) case ProjectFile::enumValue: return #enumValue
 const char *projectFileKindToText(ProjectFile::Kind kind)
 {