[ObjC ARC] Converts ios/chrome/browser/ui/util:util to ARC.

ios/chrome/browser/ui/util/core_text_util.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/browser/ui/util/core_text_util.h"
 
 #import <UIKit/UIKit.h>
 
 #include "base/i18n/rtl.h"
 #include "base/mac/foundation_util.h"
-#include "base/mac/scoped_nsobject.h"
 #import "ios/chrome/browser/ui/util/manual_text_framer.h"
 #import "ios/chrome/browser/ui/util/text_frame.h"
 #import "ios/chrome/browser/ui/util/unicode_util.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace core_text_util {
 
 namespace {
 // Returns the range within |string| for which |text_frame|'s glyph information
 // is non-repeating.
 CFRange GetValidRangeForTextFrame(CTFrameRef text_frame,
                                   NSAttributedString* string) {
   DCHECK(text_frame);
   DCHECK(string.length);
   CFRange range = CFRangeMake(0, 0);
   bool is_rtl =
       GetEffectiveWritingDirection(string) == NSWritingDirectionRightToLeft;
   for (id line_id in base::mac::CFToNSCast(CTFrameGetLines(text_frame))) {
-    CTLineRef line = static_cast<CTLineRef>(line_id);
+    CTLineRef line = (__bridge CTLineRef)(line_id);

[marq (ping after 24h), 2017/04/21 16:25:04]

We should still use static_cast<>() even if we're using __bridge, right?

[sdefresne, 2017/04/24 11:30:02]

Sadly "bridge" and "static_cast" don't mix. This is why we have a
BASE_MAC_BRIDGE_CAST in base/mac/scoped_block.h.

     NSArray* runs = base::mac::CFToNSCast(CTLineGetGlyphRuns(line));
     NSInteger run_idx = is_rtl ? runs.count - 1 : 0;
     while (run_idx >= 0 && run_idx < static_cast<NSInteger>(runs.count)) {
-      CTRunRef run = static_cast<CTRunRef>(runs[run_idx]);
+      CTRunRef run = (__bridge CTRunRef)(runs[run_idx]);
       CFRange run_range = CTRunGetStringRange(run);
       if (run_range.location == range.location + range.length)
         range.length += run_range.length;
       else
         break;
       run_idx += is_rtl ? -1 : 1;
     }
   }
   return range;
 }
@@ skipping 173 matching lines @@
                                       atIndex:0
                                effectiveRange:nullptr];
   if (style && style.baseWritingDirection != NSWritingDirectionNatural) {
     // Use the NSParagraphStyle's writing direction if specified.
     direction = style.baseWritingDirection;
   }
   return direction;
 }
 
 }  // namespace core_text_util