Moves include of objc_property_releaser out of a header.

ios/chrome/browser/snapshots/snapshot_cache.mm

Index: ios/chrome/browser/snapshots/snapshot_cache.mm
diff --git a/ios/chrome/browser/snapshots/snapshot_cache.mm b/ios/chrome/browser/snapshots/snapshot_cache.mm
index 8e85668ae48271691c70ad82cb1c9771ead3f9f6..d648eba7c3002203e32e2bbe291057bdde45e343 100644
--- a/ios/chrome/browser/snapshots/snapshot_cache.mm
+++ b/ios/chrome/browser/snapshots/snapshot_cache.mm
@@ -13,11 +13,14 @@
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/mac/bind_objc_block.h"
+#include "base/mac/objc_property_releaser.h"
 #include "base/mac/scoped_cftyperef.h"
+#include "base/mac/scoped_nsobject.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/task_runner_util.h"
 #include "base/threading/thread_restrictions.h"
 #include "ios/chrome/browser/experimental_flags.h"
+#import "ios/chrome/browser/snapshots/lru_cache.h"
 #import "ios/chrome/browser/snapshots/snapshot_cache_internal.h"
 #include "ios/chrome/browser/ui/ui_util.h"
 #import "ios/chrome/browser/ui/uikit_ui_util.h"
@@ -129,7 +132,34 @@ void ConvertAndSaveGreyImage(
 
 }  // anonymous namespace
 
-@implementation SnapshotCache
+@implementation SnapshotCache {
+  // Dictionary to hold color snapshots in memory. n.b. Color snapshots are not
+  // kept in memory on tablets.
+  base::scoped_nsobject<NSMutableDictionary> imageDictionary_;
+
+  // Cache to hold color snapshots in memory. n.b. Color snapshots are not
+  // kept in memory on tablets. It is used in place of the imageDictionary_ when
+  // the LRU cache snapshot experiment is enabled.
+  base::scoped_nsobject<LRUCache> lruCache_;
+
+  // Temporary dictionary to hold grey snapshots for tablet side swipe. This
+  // will be nil before -createGreyCache is called and after -removeGreyCache
+  // is called.
+  base::scoped_nsobject<NSMutableDictionary> greyImageDictionary_;
+  NSSet* pinnedIDs_;
+
+  // Session ID of most recent pending grey snapshot request.
+  base::scoped_nsobject<NSString> mostRecentGreySessionId_;
+  // Block used by pending request for a grey snapshot.
+  base::scoped_nsprotocol<GreyBlock> mostRecentGreyBlock_;
+
+  // Session ID and correspoinding UIImage for the snapshot that will likely
+  // be requested to be saved to disk when the application is backgrounded.
+  base::scoped_nsobject<NSString> backgroundingImageSessionId_;
+  base::scoped_nsobject<UIImage> backgroundingColorImage_;
+
+  base::mac::ObjCPropertyReleaser propertyReleaser_SnapshotCache_;
+}
 
 @synthesize pinnedIDs = pinnedIDs_;