WebUSB: Refactor code to close serial terminal into own function.

Same code was in 3 different places.
Now when the serial button is used to close the terminal the
terminal itself is reset as well, as it can be deceiving to have
the old content when the micro:bit serial is reset on reconnects.

Author: microbit-carlos

python-main.js

@@ -1484,16 +1484,8 @@ function web_editor(config) {
 
         // Hide serial and disconnect if open
         if ($("#repl").css('display') != 'none') {
-            $("#repl").hide();
-            $("#request-repl").hide();
-            $("#request-serial").hide();
-            $("#editor-container").show();
+            closeSerial();
         }
-        $("#command-serial").attr("title", config["translate"]["static-strings"]["buttons"]["command-serial"]["title"]);
-        $("#command-serial > .roundlabel").text(config["translate"]["static-strings"]["buttons"]["command-serial"]["label"]);
-
-        $("#repl").empty();
-        REPL = null;
 
         // Change button to connect
         $("#command-disconnect").hide();
@@ -1509,15 +1501,13 @@ function web_editor(config) {
         if (usePartialFlashing) {
             if (window.dapwrapper) {
                 console.log("Disconnecting: Using Quick Flash");
-                p = p.then(function() { window.dapwrapper.daplink.stopSerialRead() } )
-                    .then(function() { window.dapwrapper.disconnectAsync() } );
+                p = p.then(function() { window.dapwrapper.disconnectAsync() } );
             }
         }
         else {
             if (window.daplink) {
                 console.log("Disconnecting: Using Full Flash");
-                p = p.then(function() { window.daplink.stopSerialRead() } )
-                    .then(function() { window.daplink.disconnect() } );
+                p = p.then(function() { window.daplink.disconnect() } );
             }
         }
 
@@ -1538,21 +1528,7 @@ function web_editor(config) {
 
         // Hide serial and disconnect if open
         if ($("#repl").css('display') != 'none') {
-            $("#repl").hide();
-            $("#request-repl").hide();
-            $("#request-serial").hide();
-            $("#editor-container").show();
-            $("#command-serial").attr("title", config["translate"]["static-strings"]["buttons"]["command-serial"]["title"]);
-            $("#command-serial > .roundlabel").text(config["translate"]["static-strings"]["buttons"]["command-serial"]["label"]);
-
-            if (usePartialFlashing) {
-                if (window.dapwrapper) {
-                    window.dapwrapper.daplink.stopSerialRead();
-                }
-            }
-            else {
-                window.daplink.stopSerialRead();
-            }
+            closeSerial();
         }
 
         // Get the hex to flash in bytes format, exit if there is an error
@@ -1580,9 +1556,6 @@ function web_editor(config) {
 
         var p = Promise.resolve();
         if (usePartialFlashing) {
-            REPL = null;
-            $("#repl").empty();
-
             p = window.dapwrapper.disconnectAsync()
                 .then(function() {
                     return PartialFlashing.connectDapAsync();
@@ -1640,25 +1613,29 @@ function web_editor(config) {
         });
     }
 
+    function closeSerial(keepSession) {
+        console.log("Closing Serial Terminal");
+        $("#repl").empty();
+        $("#repl").hide();
+        $("#request-repl").hide();
+        $("#request-serial").hide();
+        $("#editor-container").show();
+
+        var serialButton = config["translate"]["static-strings"]["buttons"]["command-serial"];
+        $("#command-serial").attr("title", serialButton["title"]);
+        $("#command-serial > .roundlabel").text(serialButton["label"]);
+
+        var daplink = usePartialFlashing ? window.dapwrapper.daplink : window.daplink;
+        daplink.stopSerialRead();
+        REPL = null;
+    }
+
     function doSerial() {
         console.log("Setting Up Serial Terminal");
         // Hide terminal
         var serialButton = config["translate"]["static-strings"]["buttons"]["command-serial"];
         if ($("#repl").css('display') != 'none') {
-            $("#repl").hide();
-            $("#request-repl").hide();
-            $("#request-serial").hide();
-            $("#editor-container").show();
-            $("#command-serial").attr("title", serialButton["label"]);
-            $("#command-serial > .roundlabel").text(serialButton["label"]);
-            if (usePartialFlashing) {
-                if (window.dapwrapper) {
-                    window.dapwrapper.daplink.stopSerialRead();
-                }
-            }
-            else {
-                window.daplink.stopSerialRead();
-            }
+            closeSerial();
             return;
         }