Fix "unreachable code" warnings (MSVC warning 4702), misc. edition.

webkit/browser/fileapi/isolated_context.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.
 
 #include "webkit/browser/fileapi/isolated_context.h"
 
 #include "base/basictypes.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/rand_util.h"
@@ skipping 23 matching lines @@
     }
     name.append(1, path.value()[i]);
   }
   return name;
 #else
   return FILE_PATH_LITERAL("<root>");
 #endif
 }
 
 bool IsSinglePathIsolatedFileSystem(FileSystemType type) {
-  switch (type) {
-    // As of writing dragged file system is the only filesystem
-    // which could have multiple top-level paths.
-    case kFileSystemTypeDragged:
-      return false;
-
-    case kFileSystemTypeUnknown:
-      NOTREACHED();
-      return true;
-
-    default:
-      return true;
-  }
-  NOTREACHED();
-  return true;
+  DCHECK_NE(kFileSystemTypeUnknown, type);
+  // As of writing dragged file system is the only filesystem which could have
+  // multiple top-level paths.
+  return type != kFileSystemTypeDragged;
 }
 
 static base::LazyInstance<IsolatedContext>::Leaky g_isolated_context =
     LAZY_INSTANCE_INITIALIZER;
 
 }  // namespace
 
 IsolatedContext::FileInfoSet::FileInfoSet() {}
 IsolatedContext::FileInfoSet::~FileInfoSet() {}
 
@@ skipping 401 matching lines @@
   uint32 random_data[4];
   std::string id;
   do {
     base::RandBytes(random_data, sizeof(random_data));
     id = base::HexEncode(random_data, sizeof(random_data));
   } while (instance_map_.find(id) != instance_map_.end());
   return id;
 }
 
 }  // namespace fileapi