mshtml: Return S_OK in plugin host's CanInPlaceActivate implementation.

dlls/mshtml/pluginhost.c

@@ -875,8 +875,10 @@ static HRESULT WINAPI PHInPlaceSite_ContextSensitiveHelp(IOleInPlaceSiteEx *ifac
 static HRESULT WINAPI PHInPlaceSite_CanInPlaceActivate(IOleInPlaceSiteEx *iface)
 {
     PluginHost *This = impl_from_IOleInPlaceSiteEx(iface);
-    FIXME("(%p)\n", This);
-    return E_NOTIMPL;
+
+    TRACE("(%p)\n", This);
+
+    return S_OK;
 }
 
 static HRESULT WINAPI PHInPlaceSite_OnInPlaceActivate(IOleInPlaceSiteEx *iface)

dlls/mshtml/tests/activex.c

@@ -903,6 +903,9 @@ static HRESULT WINAPI OleObject_DoVerb(IOleObject *iface, LONG iVerb, LPMSG lpms
     hres = IOleClientSite_QueryInterface(pActiveSite, &IID_IOleInPlaceSiteEx, (void**)&ip_site);
     ok(hres == S_OK, "Could not get IOleInPlaceSiteEx iface: %08x\n", hres);
 
+    hres = IOleInPlaceSiteEx_CanInPlaceActivate(ip_site);
+    ok(hres == S_OK, "CanInPlaceActivate failed: %08x\n", hres);
+
     SET_EXPECT(InPlaceObject_GetWindow);
     no_redraw = 0xdeadbeef;
     hres = IOleInPlaceSiteEx_OnInPlaceActivateEx(ip_site, &no_redraw, 0);