Build the Flush Dialog Page URLs with the Shared Helper

WipingDialog and NozzleListTable still called
wxFileSystem::FileNameToURL directly. They now go through
file_url_from_path like every other local page, so the URLs are built
in one place.

Adds a test for a resources directory with a '#' in its name, which the
plugin page check did not recognise before.

src/slic3r/GUI/Widgets/MultiNozzleSync.cpp

@@ -1,5 +1,6 @@
 #include "MultiNozzleSync.hpp"
 
+#include "../GUI.hpp"
 #include "../GUI_App.hpp"
 #include "../I18N.hpp"
 #include "../Plater.hpp"
@@ -21,8 +22,6 @@
 #include <set>
 
 #include <wx/choice.h>
-#include <wx/filename.h>
-#include <wx/filesys.h>
 #include <wx/sizer.h>
 #include <wx/stattext.h>
 
@@ -641,8 +640,7 @@ NozzleListTable::NozzleListTable(wxWindow* parent) : wxPanel(parent,wxID_ANY,wxD
     m_web_view->AddScriptMessageHandler("nozzleListTable");
     m_web_view->EnableContextMenu(false);
     fs::path filepath = fs::path(resources_dir()) / "web/flush/NozzleListTable.html";
-    wxFileName fn(wxString::FromUTF8(filepath.string()));
-    wxString url = wxFileSystem::FileNameToURL(fn);
+    wxString url = file_url_from_path(filepath);
     m_web_view->LoadURL(url);
 
     auto sizer = new wxBoxSizer(wxVERTICAL);

src/slic3r/GUI/WipeTowerDialog.cpp

@@ -464,7 +464,7 @@ WipingDialog::WipingDialog(wxWindow* parent, const int max_flush_volume) :
     wxString filepath_str = from_path(filepath);
     wxFileName fn(filepath_str);
     if(fn.FileExists()) {
-        wxString url = wxFileSystem::FileNameToURL(fn);
+        wxString url = file_url_from_path(filepath);
         BOOST_LOG_TRIVIAL(debug) << __FUNCTION__<< "File exists and load url " << url.ToStdString();
         m_webview->LoadURL(url);
         BOOST_LOG_TRIVIAL(debug) << __FUNCTION__<< "Successfully loaded url: " << url.ToStdString();

tests/slic3rutils/test_plugin_host_api.cpp

@@ -228,6 +228,17 @@ TEST_CASE("A reloaded plugin page is recognised by its base URL, fragment aside"
     CHECK_FALSE(is_content_url(""));
 }
 
+TEST_CASE("A reloaded plugin page is recognised when the resources path holds a '#'", "[PluginHost]")
+{
+    using namespace Slic3r::GUI::web_hosting;
+
+    const Slic3r::ScopedResourcesDir resources("web#content check");
+
+    CHECK(is_content_url(content_base_url()));
+    CHECK(is_content_url(content_base_url() + "#tab2"));
+    CHECK_FALSE(is_content_url(content_base_url() + "guide.html"));
+}
+
 TEST_CASE("Plugin host API exposes model geometry and structure to Python", "[PluginHost][Python]")
 {
     using Catch::Matchers::WithinAbs;