EME: Address TODOs related to the removal of prefixed EME

media/cdm/aes_decryptor.cc

Index: media/cdm/aes_decryptor.cc
diff --git a/media/cdm/aes_decryptor.cc b/media/cdm/aes_decryptor.cc
index bb5baa48c93c48efa9a5f02b4e7717d3121676a9..8c909e3a2d954777462c661d8b0352beb84f5f87 100644
--- a/media/cdm/aes_decryptor.cc
+++ b/media/cdm/aes_decryptor.cc
@@ -20,6 +20,7 @@
 #include "media/base/cdm_promise.h"
 #include "media/base/decoder_buffer.h"
 #include "media/base/decrypt_config.h"
+#include "media/base/limits.h"
 #include "media/base/video_decoder_config.h"
 #include "media/base/video_frame.h"
 #include "media/cdm/json_web_key.h"
@@ -268,47 +269,46 @@ void AesDecryptor::CreateSessionAndGenerateRequest(
   // TODO(jrummell): Validate |session_type|.
 
   std::vector<uint8_t> message;
-  // TODO(jrummell): Since unprefixed will never send NULL, remove this check
-  // when prefixed EME is removed (http://crbug.com/249976).
-  if (!init_data.empty()) {
-    std::vector<std::vector<uint8_t>> keys;
-    switch (init_data_type) {
-      case EmeInitDataType::WEBM:
-        // |init_data| is simply the key needed.
-        keys.push_back(init_data);
-        break;
-      case EmeInitDataType::CENC:
+  std::vector<std::vector<uint8_t>> keys;
+  switch (init_data_type) {
+    case EmeInitDataType::WEBM:
+      // |init_data| is simply the key needed.
+      if (init_data.size() < limits::kMinKeyIdLength ||
+          init_data.size() > limits::kMaxKeyIdLength) {
+        promise->reject(NOT_SUPPORTED_ERROR, 0, "Incorrect length");
+        return;
+      }
+      keys.push_back(init_data);
+      break;
+    case EmeInitDataType::CENC:
 #if defined(USE_PROPRIETARY_CODECS)
-        // |init_data| is a set of 0 or more concatenated 'pssh' boxes.
-        if (!GetKeyIdsForCommonSystemId(init_data, &keys)) {
-          promise->reject(NOT_SUPPORTED_ERROR, 0,
-                          "No supported PSSH box found.");
-          return;
-        }
-        break;
-#else
-        promise->reject(NOT_SUPPORTED_ERROR, 0,
-                        "Initialization data type CENC is not supported.");
+      // |init_data| is a set of 0 or more concatenated 'pssh' boxes.
+      if (!GetKeyIdsForCommonSystemId(init_data, &keys)) {
+        promise->reject(NOT_SUPPORTED_ERROR, 0, "No supported PSSH box found.");
         return;
-#endif
-      case EmeInitDataType::KEYIDS: {
-        std::string init_data_string(init_data.begin(), init_data.end());
-        std::string error_message;
-        if (!ExtractKeyIdsFromKeyIdsInitData(init_data_string, &keys,
-                                             &error_message)) {
-          promise->reject(NOT_SUPPORTED_ERROR, 0, error_message);
-          return;
-        }
-        break;
       }
-      default:
-        NOTREACHED();
-        promise->reject(NOT_SUPPORTED_ERROR, 0,
-                        "init_data_type not supported.");
+      break;
+#else
+      promise->reject(NOT_SUPPORTED_ERROR, 0,
+                      "Initialization data type CENC is not supported.");
+      return;
+#endif
+    case EmeInitDataType::KEYIDS: {
+      std::string init_data_string(init_data.begin(), init_data.end());
+      std::string error_message;
+      if (!ExtractKeyIdsFromKeyIdsInitData(init_data_string, &keys,
+                                           &error_message)) {
+        promise->reject(NOT_SUPPORTED_ERROR, 0, error_message);
         return;
+      }
+      break;
     }
-    CreateLicenseRequest(keys, session_type, &message);
+    default:
+      NOTREACHED();
+      promise->reject(NOT_SUPPORTED_ERROR, 0, "init_data_type not supported.");
+      return;
   }
+  CreateLicenseRequest(keys, session_type, &message);
 
   promise->resolve(session_id);
 
@@ -416,20 +416,8 @@ void AesDecryptor::CloseSession(const std::string& session_id,
 
 void AesDecryptor::RemoveSession(const std::string& session_id,
                                  std::unique_ptr<SimpleCdmPromise> promise) {
-  // AesDecryptor doesn't keep any persistent data, so this should be
-  // NOT_REACHED().
-  // TODO(jrummell): Make sure persistent session types are rejected.
-  // http://crbug.com/384152.
-  //
-  // However, v0.1b calls to CancelKeyRequest() will call this, so close the
-  // session, if it exists.
-  // TODO(jrummell): Remove the close() call when prefixed EME is removed.
-  // http://crbug.com/249976.
-  if (valid_sessions_.find(session_id) != valid_sessions_.end()) {
-    CloseSession(session_id, std::move(promise));
-    return;
-  }
-
+  // See https://crbug.com/416194.
+  NOTREACHED() << "AesDecryptor doesn't support persistent sessions.";
   promise->reject(INVALID_ACCESS_ERROR, 0, "Session does not exist.");
 }