Move some sniffer arrays to read-only data segment

net/base/mime_sniffer.cc

 // Copyright (c) 2012 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.
 
 // Detecting mime types is a tricky business because we need to balance
 // compatibility concerns with security issues.  Here is a survey of how other
 // browsers behave and then a description of how we intend to behave.
 //
 // HTML payload, no Content-Type header:
 // * IE 7: Render as HTML
@@ skipping 90 matching lines @@
 #include "base/strings/string_util.h"
 #include "url/gurl.h"
 
 namespace net {
 
 // The number of content bytes we need to use all our magic numbers.  Feel free
 // to increase this number if you add a longer magic number.
 static const size_t kBytesRequiredForMagic = 42;
 
 struct MagicNumber {
-  const char* const mime_type;
-  const char* const magic;
+  const char* mime_type;
+  const char* magic;
   size_t magic_len;
   bool is_string;
-  const char* const mask;  // if set, must have same length as |magic|
+  const char* mask;  // if set, must have same length as |magic|
 };
 
 #define MAGIC_NUMBER(mime_type, magic) \
   { (mime_type), (magic), sizeof(magic)-1, false, NULL },
 
 template <int MagicSize, int MaskSize>
 class VerifySizes {
   static_assert(MagicSize == MaskSize, "sizes must be equal");
 
  public:
@@ skipping 70 matching lines @@
 
 enum OfficeDocType {
   DOC_TYPE_WORD,
   DOC_TYPE_EXCEL,
   DOC_TYPE_POWERPOINT,
   DOC_TYPE_NONE
 };
 
 struct OfficeExtensionType {
   OfficeDocType doc_type;
-  const char* const extension;
+  const char* extension;
   size_t extension_len;
 };
 
 #define OFFICE_EXTENSION(type, extension) \
   { (type), (extension), sizeof(extension) - 1 },
 
 static const OfficeExtensionType kOfficeExtensionTypes[] = {
   OFFICE_EXTENSION(DOC_TYPE_WORD, ".doc")
   OFFICE_EXTENSION(DOC_TYPE_EXCEL, ".xls")
   OFFICE_EXTENSION(DOC_TYPE_POWERPOINT, ".ppt")
@@ skipping 661 matching lines @@
       ~(1u << '\t' | 1u << '\n' | 1u << '\r' | 1u << '\f' | 1u << '\x1b');
   for (size_t i = 0; i < size; ++i) {
     uint8_t byte = static_cast<uint8_t>(content[i]);
     if (byte < 0x20 && (kBinaryBits & (1u << byte)))
       return true;
   }
   return false;
 }
 
 }  // namespace net