Clang: Ensure that platform codegen flags get also filtered

Leave the function addExtraCodeModelFlags() around as it's used by
ClangPchManager::ProjectUpdater::toolChainArguments().

This allows us to filter out excess target arguments in a follow-up
change.

Change-Id: I742d713dd1ca6c391ba77c52555dcf4e94cc2ff9
Reviewed-by: Cristian Adam <cristian.adam@qt.io>
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@qt.io>

src/plugins/cpptools/compileroptionsbuilder.cpp

@@ -140,8 +140,6 @@ QStringList CompilerOptionsBuilder::build(ProjectFile::Kind fileKind,
     addPrecompiledHeaderOptions(usePrecompiledHeaders);
     addProjectConfigFileInclude();
 
-    addExtraCodeModelFlags();
-
     addMsvcCompatibilityVersion();
     addProjectMacros();
     undefineClangVersionMacrosForMsvc();
@@ -727,7 +725,8 @@ void CompilerOptionsBuilder::evaluateCompilerFlags()
     const Core::Id &toolChain = m_projectPart.toolchainType;
     bool containsDriverMode = false;
     bool skipNext = false;
-    for (const QString &option : m_projectPart.compilerFlags) {
+    const QStringList allFlags = m_projectPart.compilerFlags + m_projectPart.extraCodeModelFlags;
+    for (const QString &option : allFlags) {
         if (skipNext) {
             skipNext = false;
             continue;

tests/unit/unittest/compileroptionsbuilder-test.cpp

@@ -593,14 +593,14 @@ TEST_F(CompilerOptionsBuilder, BuildAllOptions)
     ASSERT_THAT(compilerOptionsBuilder.options(),
                 ElementsAre("-nostdinc",
                             "-nostdinc++",
+                            "-arch",
+                            "x86_64",
                             "-fsyntax-only",
                             "-m64",
                             "--target=x86_64-apple-darwin10",
                             "-x",
                             "c++",
                             "-std=c++17",
-                            "-arch",
-                            "x86_64",
                             "-DprojectFoo=projectBar",
                             "-I", IsPartOfHeader("wrappedQtHeaders"),
                             "-I", IsPartOfHeader(toNative("wrappedQtHeaders/QtCore").toStdString()),