[geary/wip/yet-more-s390x-ftbs] Apply same workaround for s390x to client code as for the web extension

[Michael Gratton <mjog src gnome org>]

commit 01734f38d14d99f059453b00cf7b517df2601b11
Author: Michael Gratton <mike vee net>
Date:   Fri Mar 1 20:26:10 2019 +1100

    Apply same workaround for s390x to client code as for the web extension
    
    Apply workaround in 719b3a19 to remaing similar calls in client
    codebase.
    
    Fixes #260

 src/client/conversation-viewer/conversation-web-view.vala |  3 ++-
 src/client/util/util-webkit.vala                          | 12 +++++++-----
 2 files changed, 9 insertions(+), 6 deletions(-)
---
diff --git a/src/client/conversation-viewer/conversation-web-view.vala 
b/src/client/conversation-viewer/conversation-web-view.vala
index 48b92317..e46158f0 100644
--- a/src/client/conversation-viewer/conversation-web-view.vala
+++ b/src/client/conversation-viewer/conversation-web-view.vala
@@ -206,7 +206,8 @@ public class ConversationWebView : ClientWebView {
 
     private void on_deceptive_link_clicked(WebKit.JavascriptResult result) {
         try {
-            unowned JS.GlobalContext context = result.get_global_context();
+            unowned JS.GlobalContext context =
+                (JS.GlobalContext) result.get_global_context();
             JS.Object details = WebKitUtil.to_object(result);
 
             uint reason = (uint) Geary.JS.to_number(
diff --git a/src/client/util/util-webkit.vala b/src/client/util/util-webkit.vala
index 45a27c44..4957d1ee 100644
--- a/src/client/util/util-webkit.vala
+++ b/src/client/util/util-webkit.vala
@@ -18,7 +18,8 @@ namespace WebKitUtil {
      */
     public bool to_bool(WebKit.JavascriptResult result)
         throws Geary.JS.Error {
-        unowned JS.GlobalContext context = result.get_global_context();
+        unowned JS.GlobalContext context =
+            (JS.GlobalContext) result.get_global_context();
         unowned JS.Value value = result.get_value();
         if (!value.is_boolean(context)) {
             throw new Geary.JS.Error.TYPE("Result is not a JS Boolean object");
@@ -34,7 +35,7 @@ namespace WebKitUtil {
      */
     public inline double to_number(WebKit.JavascriptResult result)
         throws Geary.JS.Error {
-        return Geary.JS.to_number(result.get_global_context(),
+        return Geary.JS.to_number((JS.GlobalContext) result.get_global_context(),
                                   result.get_value());
     }
 
@@ -46,7 +47,7 @@ namespace WebKitUtil {
      */
     public inline string to_string(WebKit.JavascriptResult result)
         throws Geary.JS.Error {
-        return Geary.JS.to_string(result.get_global_context(),
+        return Geary.JS.to_string((JS.GlobalContext) result.get_global_context(),
                                   result.get_value());
     }
 
@@ -59,7 +60,8 @@ namespace WebKitUtil {
      */
     public string as_string(WebKit.JavascriptResult result)
         throws Geary.JS.Error {
-        unowned JS.GlobalContext context = result.get_global_context();
+        unowned JS.GlobalContext context =
+            (JS.GlobalContext) result.get_global_context();
         unowned JS.Value js_str_value = result.get_value();
         JS.Value? err = null;
         JS.String js_str = js_str_value.to_string_copy(context, out err);
@@ -78,7 +80,7 @@ namespace WebKitUtil {
      */
     public JS.Object? to_object(WebKit.JavascriptResult result)
         throws Geary.JS.Error {
-        return Geary.JS.to_object(result.get_global_context(),
+        return Geary.JS.to_object((JS.GlobalContext) result.get_global_context(),
                                   result.get_value());
     }