ClangCodeModel/TextEditor: Add support for highlighting parameters

This is already built into clang, so we just need to expose it to the
highlighter and the UI.

Fixes: QTCREATORBUG-24880
Change-Id: I6d0595af2589a9b69eb954aafad46457ab2c5752
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/clangcodemodel/clanghighlightingresultreporter.cpp

@@ -50,6 +50,8 @@ TextEditor::TextStyle toTextStyle(ClangBackEnd::HighlightingType type)
         return TextEditor::C_PRIMITIVE_TYPE;
     case HighlightingType::LocalVariable:
         return TextEditor::C_LOCAL;
+    case HighlightingType::Parameter:
+        return TextEditor::C_PARAMETER;
     case HighlightingType::Field:
     case HighlightingType::QtProperty:
         return TextEditor::C_FIELD;

src/plugins/languageclient/semantichighlightsupport.cpp

@@ -80,7 +80,7 @@ static Utils::optional<TextEditor::TextStyle> styleForScopes(const QList<QString
         {"variable.other.member", TextEditor::C_FIELD},
         {"variable.other.field", TextEditor::C_FIELD},
         {"variable.other.field.static", TextEditor::C_GLOBAL},
-        {"variable.parameter", TextEditor::C_LOCAL},
+        {"variable.parameter", TextEditor::C_PARAMETER},
     };
 
     for (QString scope : scopes) {

src/plugins/texteditor/texteditorconstants.cpp

@@ -55,6 +55,7 @@ const char *nameForStyle(TextStyle style)
     case C_STRING:              return "String";
     case C_TYPE:                return "Type";
     case C_LOCAL:               return "Local";
+    case C_PARAMETER:           return "Parameter";
     case C_GLOBAL:              return "Global";
     case C_FIELD:               return "Field";
     // TODO: Rename "Static" to "Enumeration" in next major update,

src/plugins/texteditor/texteditorconstants.h

@@ -55,6 +55,7 @@ enum TextStyle : quint8 {
     C_STRING,
     C_TYPE,
     C_LOCAL,
+    C_PARAMETER,
     C_GLOBAL,
     C_FIELD,
     C_ENUMERATION,

src/plugins/texteditor/texteditorsettings.cpp

@@ -162,6 +162,8 @@ FormatDescriptions TextEditorSettingsPrivate::initialFormats()
                              Qt::darkMagenta);
     formatDescr.emplace_back(C_LOCAL, tr("Local"),
                              tr("Local variables."), QColor(9, 46, 100));
+    formatDescr.emplace_back(C_PARAMETER, tr("Parameter"),
+                             tr("Function or method parameters."), QColor(9, 46, 100));
     formatDescr.emplace_back(C_FIELD, tr("Field"),
                              tr("Class' data members."), Qt::darkRed);
     formatDescr.emplace_back(C_GLOBAL, tr("Global"),