ClangSupport: Use simpler structures in some cases

The patch is mostly mechanical, but contains also a few spurious changes
from values references for some local variables, foreach -> ranged for
etc that I coulnd't resist.

Change-Id: I58f0bd972546895eb318607cbfbd7ac35caf3f23
Reviewed-by: Ivan Donchevskii <ivan.donchevskii@qt.io>

src/libs/clangsupport/dynamicastmatcherdiagnosticmessagecontainer.cpp

@@ -34,8 +34,8 @@ QDebug operator<<(QDebug debug, const DynamicASTMatcherDiagnosticMessageContaine
 {
     debug.nospace() << "DynamicASTMatcherDiagnosticMessageContainer("
                     << container.errorTypeText() << ", "
-                    << container.sourceRange() << ", "
-                    << container.arguments()
+                    << container.sourceRange << ", "
+                    << container.arguments
                     << ")";
 
     return debug;
@@ -43,7 +43,7 @@ QDebug operator<<(QDebug debug, const DynamicASTMatcherDiagnosticMessageContaine
 
 Utils::SmallString DynamicASTMatcherDiagnosticMessageContainer::errorTypeText() const
 {
-    switch (m_errorType) {
+    switch (errorType) {
        RETURN_CASE(None)
        RETURN_CASE(RegistryMatcherNotFound)
        RETURN_CASE(RegistryWrongArgCount)