Cancel orphan toasts

app/src/main/java/eu/faircode/email/ActivityEML.java

@@ -679,7 +679,10 @@ public class ActivityEML extends ActivityBase {
 
             @Override
             protected void onDestroyed(Bundle args) {
-                toast = null;
+                if (toast != null) {
+                    toast.cancel();
+                    toast = null;
+                }
             }
 
             @Override

app/src/main/java/eu/faircode/email/ActivitySetup.java

@@ -791,7 +791,10 @@ public class ActivitySetup extends ActivityBase implements FragmentManager.OnBac
 
             @Override
             protected void onDestroyed(Bundle args) {
-                toast = null;
+                if (toast != null) {
+                    toast.cancel();
+                    toast = null;
+                }
             }
 
             @Override

app/src/main/java/eu/faircode/email/AdapterRule.java

@@ -413,7 +413,10 @@ public class AdapterRule extends RecyclerView.Adapter<AdapterRule.ViewHolder> {
 
                         @Override
                         protected void onDestroyed(Bundle args) {
-                            toast = null;
+                            if (toast != null) {
+                                toast.cancel();
+                                toast = null;
+                            }
                         }
 
                         @Override

app/src/main/java/eu/faircode/email/FragmentCompose.java

@@ -2397,7 +2397,10 @@ public class FragmentCompose extends FragmentBase {
 
                     @Override
                     protected void onDestroyed(Bundle args) {
-                        toast = null;
+                        if (toast != null) {
+                            toast.cancel();
+                            toast = null;
+                        }
                     }
 
                     @Override
@@ -2474,7 +2477,10 @@ public class FragmentCompose extends FragmentBase {
 
             @Override
             protected void onDestroyed(Bundle args) {
-                toast = null;
+                if (toast != null) {
+                    toast.cancel();
+                    toast = null;
+                }
             }
 
             @Override

app/src/main/java/eu/faircode/email/FragmentContacts.java

@@ -498,7 +498,10 @@ public class FragmentContacts extends FragmentBase {
 
             @Override
             protected void onDestroyed(Bundle args) {
-                toast = null;
+                if (toast != null) {
+                    toast.cancel();
+                    toast = null;
+                }
             }
 
             @Override
@@ -597,7 +600,10 @@ public class FragmentContacts extends FragmentBase {
 
             @Override
             protected void onDestroyed(Bundle args) {
-                toast = null;
+                if (toast != null) {
+                    toast.cancel();
+                    toast = null;
+                }
             }
 
             @Override