[ios] Plumb SnapshotCache into tab grid.

ios/clean/chrome/browser/ui/tab_grid/tab_grid_coordinator.mm

Index: ios/clean/chrome/browser/ui/tab_grid/tab_grid_coordinator.mm
diff --git a/ios/clean/chrome/browser/ui/tab_grid/tab_grid_coordinator.mm b/ios/clean/chrome/browser/ui/tab_grid/tab_grid_coordinator.mm
index 71d1c4e7d05d355c986fca03b2684fd49f1deeef..41f56681f9fec075c6be8b31e89d10c8e98239a2 100644
--- a/ios/clean/chrome/browser/ui/tab_grid/tab_grid_coordinator.mm
+++ b/ios/clean/chrome/browser/ui/tab_grid/tab_grid_coordinator.mm
@@ -76,6 +76,7 @@
 
   self.viewController = [[TabGridViewController alloc] init];
   self.viewController.dispatcher = static_cast<id>(self.browser->dispatcher());
+  self.viewController.snapshotCache = [self snapshotCache];
 
   self.mediator.consumer = self.viewController;
 
@@ -286,12 +287,17 @@
   __weak TabGridCoordinator* weakSelf = self;
   webState->TakeSnapshot(
       base::BindBlockArc(^(const gfx::Image& snapshot) {
-        SnapshotCache* snapshotCache = SnapshotCacheFactory::GetForBrowserState(
-            weakSelf.browser->browser_state());
-        [snapshotCache setImage:snapshot.ToUIImage() withSessionID:tabID];
+        [[weakSelf snapshotCache] setImage:snapshot.ToUIImage()
+                             withSessionID:tabID];
         [weakSelf.viewController updateSnapshotAtIndex:index];
       }),
       kTabCollectionTabCellSize);
 }
 
+// Returns the snapshot cache for this browser state.
+- (SnapshotCache*)snapshotCache {

[marq (ping after 24h), 2017/07/06 12:44:50]

This feels like it should be a readonly property.

[edchin, 2017/07/07 03:18:11]

Done.

+  return SnapshotCacheFactory::GetForBrowserState(
+      self.browser->browser_state());
+}
+
 @end