[ios] Fixes InfobarCoordinator <-> Consumer memory leak.

There was a retain cycle per bug 1004690.
The ContainerCoordinator had a strong pointer to the Mediator, which in
turn had a strong pointer to infobar_container_ios, which had a strong
pointer to its consumer (ContainerCoordinator).

This would only happen on non Messages, since on the legacy implementation
the consumer is the ContainerViewController. Still I think both consumers
should be weakly retained since the mediator(infobar_container_ios)
don't really own these objects.

Bug: 1004690
Change-Id: Ic5d30b444177e216ffe2f8cdce9b0cf7d012383c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1809744Reviewed-by: Chris Lu <thegreenfrog@chromium.org>
Commit-Queue: Sergio Collazos <sczs@chromium.org>
Cr-Commit-Position: refs/heads/master@{#697490}

ios/chrome/browser/infobars/infobar_container_ios.h

@@ -35,9 +35,9 @@ class InfoBarContainerIOS : public infobars::InfoBarContainer {
   void PlatformSpecificInfoBarStateChanged(bool is_animating) override;
 
  private:
-  id<InfobarContainerConsumer> consumer_;
-  id<InfobarContainerConsumer> legacyConsumer_;
   infobars::InfoBarManager* info_bar_manager_ = nullptr;
+  __weak id<InfobarContainerConsumer> consumer_;
+  __weak id<InfobarContainerConsumer> legacyConsumer_;
 
   DISALLOW_COPY_AND_ASSIGN(InfoBarContainerIOS);
 };

ios/chrome/browser/ui/infobars/infobar_container_coordinator_unittest.mm

@@ -327,7 +327,7 @@ TEST_F(InfobarContainerCoordinatorTest,
 // TODO(crbug.com/1004514): This test fails due to
 // infobarBannerWasDismissed:forWebState:.
 TEST_F(InfobarContainerCoordinatorTest,
-       DISABLED_TestInfobarBannerDismissAtWebStateChange) {
+       TestInfobarBannerDismissAtWebStateChange) {
   AddInfobar();
   AddSecondWebstate();
 
@@ -429,7 +429,7 @@ TEST_F(InfobarContainerCoordinatorTest,
 // TODO(crbug.com/1004514): This test fails due to
 // infobarBannerWasDismissed:forWebState:.
 TEST_F(InfobarContainerCoordinatorTest,
-       DISABLED_TestInfobarBannerDismissedClosingWebstate) {
+       TestInfobarBannerDismissedClosingWebstate) {
   AddInfobar();
   // Close the Webstate without calling WaitUntilConditionOrTimeout.
   web_state_list_->CloseWebStateAt(0, 0);
@@ -445,8 +445,7 @@ TEST_F(InfobarContainerCoordinatorTest,
 // Tests that the Infobar is dismissed when both the VC and Webstate are closed.
 // TODO(crbug.com/1004514): This test fails due to
 // infobarBannerWasDismissed:forWebState:.
-TEST_F(InfobarContainerCoordinatorTest,
-       DISABLED_TestDismissingAndClosingWebstate) {
+TEST_F(InfobarContainerCoordinatorTest, TestDismissingAndClosingWebstate) {
   AddInfobar();
   ASSERT_TRUE(base::test::ios::WaitUntilConditionOrTimeout(
       base::test::ios::kWaitForUIElementTimeout, ^bool {
@@ -473,7 +472,7 @@ TEST_F(InfobarContainerCoordinatorTest,
 // TODO(crbug.com/1004514): This test fails due to
 // infobarBannerWasDismissed:forWebState:.
 TEST_F(InfobarContainerCoordinatorTest,
-       DISABLED_TestDismissingAndClosingWebstateSecondWebstate) {
+       TestDismissingAndClosingWebstateSecondWebstate) {
   AddInfobar();
   AddSecondWebstate();
   EXPECT_TRUE(base::test::ios::WaitUntilConditionOrTimeout(