Utils: More forward declarations / drop unused headers [P-R]

Round 1 - focus on headers.
For classes with initial in range [P-R].
Try to keep the same separators between different kind of headers.

Change-Id: I01fb80b93164a7fe4c0bd2cd8f9e4f27523efefa
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: hjk <hjk@qt.io>
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>

src/libs/utils/pathchooser.cpp

@@ -27,6 +27,7 @@
 
 #include "commandline.h"
 #include "environment.h"
+#include "fileutils.h"
 #include "hostosinfo.h"
 #include "macroexpander.h"
 #include "qtcassert.h"
@@ -231,7 +232,7 @@ FilePath PathChooserPrivate::expandedPath(const QString &input) const
     case PathChooser::File:
     case PathChooser::SaveFile:
         if (!m_baseDirectory.isEmpty()) {
-            Utils::FilePath fp = m_baseDirectory.resolvePath(path.path()).absoluteFilePath();
+            FilePath fp = m_baseDirectory.resolvePath(path.path()).absoluteFilePath();
             // FIXME bad hotfix for manually editing PathChooser (invalid paths, jumping cursor)
             // examples: have an absolute path and try to change the device letter by typing the new
             // letter and removing the original afterwards ends up in