[FIX] web: actionService reports: pass action's context to download

Before this commit, the report action's context was not passed to the download route.
This was problematic as some crucial keys may be forgotten when downloading the pdf.

After this commit, we do pass the full context to the download route, ensuring consistency of the context
across calls.

closes odoo/odoo#126963

Related: odoo/enterprise#43441
Signed-off-by: Luca Vitali (luvi) <luvi@odoo.com>

addons/web/static/src/webclient/actions/action_service.js

@@ -1081,11 +1081,15 @@ function makeActionManager(env) {
             let success, message;
             env.services.ui.block();
             try {
+                const downloadContext = { ...env.services.user.context };
+                if (action.context) {
+                    Object.assign(downloadContext, action.context);
+                }
                 ({ success, message } = await downloadReport(
                     env.services.rpc,
                     action,
                     type,
-                    env.services.user.context
+                    downloadContext
                 ));
             } finally {
                 env.services.ui.unblock();

addons/web/static/tests/webclient/actions/reports/report_action_tests.js

@@ -318,10 +318,14 @@ QUnit.module("ActionManager", (hooks) => {
     });
 
     QUnit.test("context is correctly passed to the client action report", async (assert) => {
-        assert.expect(8);
+        assert.expect(9);
 
         mockDownload((options) => {
             assert.step(options.url);
+            assert.deepEqual(
+                options.data.context,
+                `{"lang":"en","uid":7,"tz":"taht","rabbia":"E Tarantella","active_ids":[99]}`
+            );
             assert.deepEqual(JSON.parse(options.data.data), [
                 "/report/pdf/ennio.morricone/99",
                 "qweb-pdf",