Various Dark Theme fixes per QA feedback (#1212)

* Fix CORS issue on in-line theming javascript

* Fix date picker icon color

* Add comment

* Fix table theming in dark mode

* Selfhosted navbar fix

* Rename selector to avoid clashing with bootstrap

* Do not set initial theme if default

* Fix .text-danger style in dropdown lists

* Fix toast style, restructure toast and card scss

* Fix table and dropdown list hover color

* Use callout component for Disable Send warning

* Remove unneeded theming for hovering over links

* Undo changes to register enterprise2 layout

* Apply theming to Safari input field icons

e.g. Caps lock, password autofill

* Selectively apply themed logo CSS

* Fix unrelated linting

* Fix webpack config to bundle theme.js

Co-authored-by: Danny Murphy <6512845+dltmurphy@users.noreply.github.com>

src/theme.js

@@ -0,0 +1,22 @@
+// Set theme on page load
+// This is done outside the Angular app to avoid a flash of unthemed content before it loads
+// The defaultTheme is also set in the html itself to make sure that some theming is always applied
+(function () {
+    const defaultTheme = 'light'
+    const htmlEl = document.documentElement;
+    let theme = defaultTheme;
+
+    const savedTheme = window.localStorage.getItem('theme');
+    if (savedTheme != null) {
+        if (savedTheme.indexOf('system') > -1) {
+            theme = window.matchMedia('(prefers-color-scheme: dark)').matches ? 'dark' : 'light';
+        } else if (savedTheme.indexOf('dark') > -1) {
+            theme = 'dark';
+        }
+    }
+
+    if (!htmlEl.classList.contains('theme_' + theme)) {
+        htmlEl.classList.remove('theme_' + defaultTheme);
+        htmlEl.classList.add('theme_' + theme);
+    }
+})();