[FIX] component: strict check of deep argument truth value

With this commit, we make sure that the `render` method was explicitely
called with the deep === true argument, instead of assuming that it is a
boolean.  This prevents errors when some unrelated value is given to the
render method. This could happen in some cases, such as

useBus(someBus, 'someevent', this.render)

In that case, the `useBus` code would simply call the this.render with a
customevent, which would be considered truthy before, and not anymore

tests/components/__snapshots__/rendering.test.ts.snap

@@ -127,6 +127,30 @@ exports[`rendering semantics props are reactive 2`] = `
 }"
 `;
 
+exports[`rendering semantics render need a boolean = true to be 'deep' 1`] = `
+"function anonymous(bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  
+  return function template(ctx, node, key = \\"\\") {
+    const b2 = text(ctx['state'].value);
+    const b3 = component(\`Child\`, {}, key + \`__1\`, node, ctx);
+    return multi([b2, b3]);
+  }
+}"
+`;
+
+exports[`rendering semantics render need a boolean = true to be 'deep' 2`] = `
+"function anonymous(bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  
+  return function template(ctx, node, key = \\"\\") {
+    return text(\`child\`);
+  }
+}"
+`;
+
 exports[`rendering semantics render with deep=true followed by render with deep=false work as expected 1`] = `
 "function anonymous(bdom, helpers
 ) {

tests/components/rendering.test.ts

@@ -102,6 +102,43 @@ describe("rendering semantics", () => {
     expect(childN).toBe(2);
   });
 
+  test("render need a boolean = true to be 'deep'", async () => {
+    let childN = 0;
+    let parentN = 0;
+    class Child extends Component {
+      static template = xml`child`;
+      setup() {
+        onRendered(() => childN++);
+      }
+    }
+
+    class Parent extends Component {
+      static template = xml`
+        <t t-esc="state.value"/>
+        <Child/>
+      `;
+      static components = { Child };
+
+      state = { value: "A" };
+      setup() {
+        onRendered(() => parentN++);
+      }
+    }
+
+    const parent = await mount(Parent, fixture);
+
+    expect(fixture.innerHTML).toBe("Achild");
+    expect(parentN).toBe(1);
+    expect(childN).toBe(1);
+
+    parent.state.value = "B";
+    parent.render("true" as any as boolean);
+    await nextTick();
+    expect(fixture.innerHTML).toBe("Bchild");
+    expect(parentN).toBe(2);
+    expect(childN).toBe(1);
+  });
+
   test("render with deep=true followed by render with deep=false work as expected", async () => {
     class Child extends Component {
       static template = xml`child<t t-esc="env.getValue()"/>`;