Use real UTC for calendar-query REPORTs

build.gradle

 
 buildscript {
     ext.kotlin_version = '1.2.31'
-    ext.dokka_version = '0.9.15'
+    ext.dokka_version = '0.9.16'
 
     repositories {
         jcenter()

src/main/java/at/bitfire/dav4android/DavCalendar.kt

@@ -26,9 +26,12 @@ class DavCalendar @JvmOverloads constructor(
     companion object {
         val MIME_ICALENDAR = MediaType.parse("text/calendar")
         val MIME_ICALENDAR_UTF8 = MediaType.parse("text/calendar;charset=utf-8")
-    }
 
-    private val timeFormatUTC = SimpleDateFormat("yyyyMMdd'T'HHmmss'Z'", Locale.US)
+        private val timeFormatUTC = SimpleDateFormat("yyyyMMdd'T'HHmmss'Z'", Locale.US)
+        init {
+            timeFormatUTC.timeZone = TimeZone.getTimeZone("UTC")
+        }
+    }
 
 
     /**