Updates PhysicalWebScanner to use the new CBManagerState enum.

ios/chrome/common/physical_web/physical_web_scanner.mm

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "ios/chrome/common/physical_web/physical_web_scanner.h"
 
 #include <string>
 #include <vector>
 
 #import <CoreBluetooth/CoreBluetooth.h>
@@ skipping 96 matching lines @@
   centralManager_.reset();
   [super dealloc];
 }
 
 - (void)start {
   [self stop];
   [finalUrls_ removeAllObjects];
   [devicesUrls_ removeAllObjects];
   [devices_ removeAllObjects];
   started_ = YES;
-  if ([centralManager_ state] == CBCentralManagerStatePoweredOn)
+  if ([self bluetoothEnabled])
     [self reallyStart];
   else
     pendingStart_ = YES;
 }
 
 - (void)stop {
   if (!started_)
     return;
   for (PhysicalWebRequest* request in pendingRequests_.get()) {
     [request cancel];
   }
   [pendingRequests_ removeAllObjects];
-  if (!pendingStart_ &&
-      [centralManager_ state] == CBCentralManagerStatePoweredOn) {
+  if (!pendingStart_ && [self bluetoothEnabled]) {
     [centralManager_ stopScan];
   }
   pendingStart_ = NO;
   started_ = NO;
 }
 
 - (NSArray*)devices {
   return [devices_ sortedArrayUsingComparator:^(id obj1, id obj2) {
     PhysicalWebDevice* device1 = obj1;
     PhysicalWebDevice* device2 = obj2;
@@ skipping 21 matching lines @@
     [self requestMetadataForDevice:device];
   }
   [unresolvedDevices_ removeAllObjects];
 }
 
 - (int)unresolvedBeaconsCount {
   return [unresolvedDevices_ count];
 }
 
 - (BOOL)bluetoothEnabled {
+// TODO(crbug.com/619982): The CBManager base class appears to still be in
+// flux.  Unwind this #ifdef once the APIs settle.
+#if defined(__IPHONE_10_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_10_0
+  return [centralManager_ state] == CBManagerStatePoweredOn;
+#else
   return [centralManager_ state] == CBCentralManagerStatePoweredOn;
+#endif
 }
 
 - (void)reallyStart {
   pendingStart_ = NO;
   NSArray* serviceUUIDs = @[
     [CBUUID UUIDWithString:kUriBeaconServiceUUID],
     [CBUUID UUIDWithString:kEddystoneBeaconServiceUUID]
   ];
   [centralManager_ scanForPeripheralsWithServices:serviceUUIDs options:nil];
 }
 
 #pragma mark -
 #pragma mark CBCentralManagerDelegate methods
 
 - (void)centralManagerDidUpdateState:(CBCentralManager*)central {
-  if ([centralManager_ state] == CBCentralManagerStatePoweredOn) {
+  if ([self bluetoothEnabled]) {
     if (pendingStart_)
       [self reallyStart];
   } else {
     if (started_ && !pendingStart_) {
       pendingStart_ = YES;
       [centralManager_ stopScan];
     }
   }
   [delegate_ scannerBluetoothStatusUpdated:self];
 }
@@ skipping 116 matching lines @@
         [strongSelf.get()->devices_ addObject:device];
         [strongSelf.get()->delegate_ scannerUpdatedDevices:weakSelf];
         [strongSelf.get()->finalUrls_ addObject:[device url]];
       }
     }
     [strongSelf.get()->pendingRequests_ removeObject:strongRequest];
   }];
 }
 
 @end