Fix possible loss of data warnings in media_unittests

media/cdm/cenc_utils_unittest.cc

 // 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.
 
 #include "media/cdm/cenc_utils.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include "base/logging.h"
@@ skipping 141 matching lines @@
     box.push_back(0);
     return box;
   }
 
   void AppendData(std::vector<uint8_t>& pssh_box,
                   const std::vector<uint8_t>& data) {
     // This assumes that |pssh_box| has been created using the routines above,
     // and simply appends the data to the end of it. It updates the box size
     // and sets the data size.
     DCHECK(data.size() < 100);
-    pssh_box[3] += data.size();
+    pssh_box[3] += static_cast<uint8_t>(data.size());
     pssh_box.pop_back();
-    pssh_box.push_back(data.size());
+    pssh_box.push_back(static_cast<uint8_t>(data.size()));
     pssh_box.insert(pssh_box.end(), data.begin(), data.end());
   }
 
   const std::vector<uint8_t>& Key1() { return key1_; }
   const std::vector<uint8_t>& Key2() { return key2_; }
   const std::vector<uint8_t>& Key3() { return key3_; }
   const std::vector<uint8_t>& Key4() { return key4_; }
   const std::vector<uint8_t>& CommonSystemSystemId() {
     return common_system_system_id_;
   }
@@ skipping 102 matching lines @@
   }
 }
 
 TEST_F(CencUtilsTest, PsshBoxLargerThanSize) {
   std::vector<uint8_t> box = MakePSSHBox(1, Key1(), Key2());
   KeyIdList key_ids;
 
   // Add 20 additional bytes to |box|.
   size_t original_size = box.size();
   for (size_t i = 0; i < 20; ++i)
-    box.push_back(i);
+    box.push_back(static_cast<uint8_t>(i));
 
   // Tries every size greater than |original_size|.
   for (size_t i = original_size + 1; i < box.size(); ++i) {
     // Modify size of box passed to be less than current size.
     std::vector<uint8_t> truncated(&box[0], &box[0] + i);
     EXPECT_FALSE(ValidatePsshInput(truncated)) << "Failed for length " << i;
     EXPECT_FALSE(GetKeyIdsForCommonSystemId(truncated, &key_ids));
   }
 }
 
@@ skipping 249 matching lines @@
   EXPECT_FALSE(ValidatePsshInput(boxes));
 
   // Repeat with |non_pssh_box| first.
   boxes.clear();
   boxes.insert(boxes.end(), non_pssh_box.begin(), non_pssh_box.end());
   boxes.insert(boxes.end(), pssh_box.begin(), pssh_box.end());
   EXPECT_FALSE(ValidatePsshInput(boxes));
 }
 
 }  // namespace media