simplify the build phase

pkgs/applications/networking/charles/default.nix

@@ -6,7 +6,7 @@ let
     desktopName = "Charles";
     exec = "charles %F";
     genericName  = "Web Debugging Proxy";
-    icon = "charles";
+    icon = "charles-proxy";
     mimeType = "application/x-charles-savedsession;application/x-charles-savedsession+xml;application/x-charles-savedsession+json;application/har+json;application/vnd.tcpdump.pcap;application/x-charles-trace";
     name = "Charles";
     startupNotify = "true";
@@ -22,14 +22,8 @@ in stdenv.mkDerivation rec {
   };
 
   installPhase = ''
-    set -e
-
     mkdir -pv $out/bin
 
-    for fn in lib/*.jar; do
-      install -D -m644 $fn $out/$fn
-    done
-
     cat > $out/bin/charles << EOF
     #!${stdenv.shell}
 
@@ -38,20 +32,15 @@ in stdenv.mkDerivation rec {
 
     chmod +x $out/bin/charles
 
+    for fn in lib/*.jar; do
+      install -D -m644 $fn $out/$fn
+    done
+
     mkdir -p $out/share/applications
     ln -s ${desktopItem}/share/applications/* $out/share/applications/
 
-    for dim in 16x16 32x32 64x64 128x128 256x256 512x512; do
-      install -D -m644 icon/$dim/apps/charles-proxy.png \
-        $out/share/icons/hicolor/$dim/apps/charles.png
-      for mimetype in application-har+json.png application-vnd.tcpdump.pcap.png application-x-charles-savedsession.png application-x-charles-trace.png; do
-        install -D -m644 icon/$dim/mimetypes/$mimetype \
-          $out/share/icons/hicolor/$dim/mimetypes/$mimetype
-      done
-    done
-
-    install -D -m644 doc/licenses/bounce-license.txt \
-      $out/share/licenses/bounce-license.txt
+    mkdir -p $out/share/icons
+    cp -r icon $out/share/icons/hicolor
   '';
 
   meta = with stdenv.lib; {