Remove "dark" draw option, keep only as URL parameter

Author: linev

demo/examples_more.json

@@ -225,6 +225,6 @@
      { "name": "crown", "file": "tutorials_graphics.root", "item": "crown",  "title": "TCrown, tutorials/graphics/crown.C" },
      { "name": "zstd", "file": "zstd.root", "item": "ccdb_object", "zstd": true, "title": "File with ZSTD compression, required zstd-codec.js script" },
      { "name": "pave", "file": "tpavetext.root", "item": "ccdb_object", "title": "Drawing of plain TPaveText with TLine and custom text lines alignment" },
-     { "name": "dark", "opt": "dark", "file": "hsimple.root", "item": "hpx;1", "title": "Invert colors of histogram drawing, same as settings.DarkMode = true", "notest": true }
+     { "name": "dark", "url": "?nobrowser&file=$$$hsimple.root&item=hpx;1&dark", "title": "Invert colors of histogram drawing, providing &dark in URL", "notest": true }
    ]
 }

modules/hist2d/THistPainter.mjs

@@ -305,8 +305,6 @@ class THistDrawOptions {
          return false;
       };
 
-      if (d.check('DARK')) this.darkMode = true;
-
       if (d.check('FILL_', true) && d.getColor())
          this.histoFillColor = d.color;
 
@@ -1183,10 +1181,6 @@ class THistPainter extends ObjectPainter {
          fp.createXY2(opts);
 
          return fp.drawAxes2(opts.second_x, opts.second_y);
-      } else if (this.options.darkMode) {
-         let pp = this.getPadPainter();
-         console.log('Apply dark mode', pp?.iscan);
-         if (pp?.changeDarkMode) pp.changeDarkMode(true);
       }
 
       if (this.options.adjustFrame) {