Revert of [ObjC ARC] Converts crw_web_controller to ARC.

ios/web/web_state/ui/crw_web_controller.h

Index: ios/web/web_state/ui/crw_web_controller.h
diff --git a/ios/web/web_state/ui/crw_web_controller.h b/ios/web/web_state/ui/crw_web_controller.h
index 52a698b506dc67b4c865c121c77a36cbe5e89a61..ba47f21d433b997ec2aca452a2a9d87af03e1f91 100644
--- a/ios/web/web_state/ui/crw_web_controller.h
+++ b/ios/web/web_state/ui/crw_web_controller.h
@@ -72,31 +72,31 @@
 // Defaults to NO; this should be enabled before attempting to access the view.
 @property(nonatomic, assign) BOOL webUsageEnabled;
 
-@property(nonatomic, weak) id<CRWWebDelegate> delegate;
+@property(nonatomic, assign) id<CRWWebDelegate> delegate;
 @property(nonatomic, weak) id<CRWWebUserInterfaceDelegate> UIDelegate;
-@property(nonatomic, weak) id<CRWNativeContentProvider> nativeProvider;
-@property(nonatomic, weak) id<CRWSwipeRecognizerProvider>
-    swipeRecognizerProvider;
+@property(nonatomic, assign) id<CRWNativeContentProvider> nativeProvider;
+@property(nonatomic, assign)
+    id<CRWSwipeRecognizerProvider> swipeRecognizerProvider;
 @property(nonatomic, readonly) web::WebState* webState;
 @property(nonatomic, readonly) web::WebStateImpl* webStateImpl;
 
 // The container view used to display content.  If the view has been purged due
 // to low memory, this will recreate it.
-@property(nonatomic, strong, readonly) UIView* view;
+@property(nonatomic, readonly) UIView* view;
 
 // The web view proxy associated with this controller.
-@property(nonatomic, strong, readonly) id<CRWWebViewProxy> webViewProxy;
+@property(nonatomic, readonly) id<CRWWebViewProxy> webViewProxy;
 
 // The view that generates print data when printing. It is nil if printing
 // is not supported.
-@property(nonatomic, strong, readonly) UIView* viewForPrinting;
+@property(nonatomic, readonly) UIView* viewForPrinting;
 
 // Content view was reset due to low memory.  Use placeholder overlay view on
 // next creation.
-@property(nonatomic, assign) BOOL usePlaceholderOverlay;
+@property(nonatomic, readwrite, assign) BOOL usePlaceholderOverlay;
 
 // Returns the current page loading phase.
-@property(nonatomic, readonly, assign) web::LoadPhase loadPhase;
+@property(nonatomic, readonly) web::LoadPhase loadPhase;
 
 // The fraction of the page load that has completed as a number between 0.0
 // (nothing loaded) and 1.0 (fully loaded).