Add PpapiDecryptor which wraps a CDM plugin.

webkit/media/crypto/key_systems.cc

Index: webkit/media/crypto/key_systems.cc
diff --git a/webkit/media/crypto/key_systems.cc b/webkit/media/crypto/key_systems.cc
index b4aeb90b56ce84bb11f981889a09abd04ea78a84..1e8365b3fd458ede330ff912b5c6379f43b5062c 100644
--- a/webkit/media/crypto/key_systems.cc
+++ b/webkit/media/crypto/key_systems.cc
@@ -4,8 +4,6 @@
 
 #include "webkit/media/crypto/key_systems.h"
 
-#include "media/base/decryptor.h"
-#include "media/crypto/aes_decryptor.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebString.h"
 
 namespace webkit_media {
@@ -13,6 +11,7 @@ namespace webkit_media {
 namespace {
 
 const char kClearKeyKeySystem[] = "webkit-org.w3.clearkey";
+const char kExternalClearKeyKeySystem[] = "org.chromium.external-clearkey";

[ddorwin, 2012/07/19 01:12:34]

Not sure whether we should use a '-'. I guess it's fine.

[xhwang, 2012/07/19 15:54:34]

Done.

 
 struct MediaFormatAndKeySystem {
   const char* mime_type;
@@ -20,12 +19,17 @@ struct MediaFormatAndKeySystem {
   const char* key_system;
 };
 
+struct KeySystemPluginTypePair {
+  const char* key_system;
+  const char* plugin_type;
+};
+
 static const MediaFormatAndKeySystem

[xhwang, 2012/07/19 15:54:34]

We have both anonymous namespace and static function in this file. I plan to
remove anonymous namespace and use static exclusively in this file. Please let
me know if it sounds good.

[ddorwin, 2012/07/19 20:50:09]

SG. I guess both are allowed (last paragraph):
http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml?showone=Nonmem...

[xhwang, 2012/07/19 21:54:03]

Done.

 supported_format_key_system_combinations[] = {
   // TODO(ddorwin): Reconsider based on how usage of this class evolves.
   // For now, this class is stateless, so we do not have the opportunity to
   // build a list using ParseCodecString() like
-  // net::MimeUtil::InitializeMimeTypeMaps(). Therfore, the following line must
+  // net::MimeUtil::InitializeMimeTypeMaps(). Therefore, the following line must
   // be separate entries.
   // { "video/webm", "vorbis,vp8,vp8.0", kClearKeyKeySystem },
   { "video/webm", "vorbis", kClearKeyKeySystem },
@@ -33,7 +37,18 @@ supported_format_key_system_combinations[] = {
   { "video/webm", "vp8.0", kClearKeyKeySystem },
   { "audio/webm", "vorbis", kClearKeyKeySystem },
   { "video/webm", "", kClearKeyKeySystem },
-  { "audio/webm", "", kClearKeyKeySystem }
+  { "audio/webm", "", kClearKeyKeySystem },
+  { "video/webm", "vorbis", kExternalClearKeyKeySystem },
+  { "video/webm", "vp8", kExternalClearKeyKeySystem },
+  { "video/webm", "vp8.0", kExternalClearKeyKeySystem },
+  { "audio/webm", "vorbis", kExternalClearKeyKeySystem },
+  { "video/webm", "", kExternalClearKeyKeySystem },
+  { "audio/webm", "", kExternalClearKeyKeySystem }
+};
+
+static const KeySystemPluginTypePair key_system_to_plugin_type_mapping[] = {
+  // TODO(xhwang): Update this with the real plugin name.
+  { kExternalClearKeyKeySystem, "application/x-ppapi-example" }
 };
 
 bool IsSupportedKeySystemWithContainerAndCodec(const std::string& mime_type,
@@ -56,7 +71,8 @@ bool IsSupportedKeySystemWithContainerAndCodec(const std::string& mime_type,
 }  // namespace
 
 bool IsSupportedKeySystem(const WebKit::WebString& key_system) {
-  if (key_system == kClearKeyKeySystem)
+  if (key_system == kClearKeyKeySystem ||

[ddorwin, 2012/07/19 01:12:34]

We _could_ replace this with:
  if (CanUseAesDecryptor || GetPluginType()).
This avoids code duplication and maintenance costs. Thoughts?

[xhwang, 2012/07/19 15:54:34]

Done.

+      key_system == kExternalClearKeyKeySystem)
     return true;
   return false;
 }
@@ -77,11 +93,17 @@ bool IsSupportedKeySystemWithMediaMimeType(
   return true;
 }
 
-scoped_ptr<media::Decryptor> CreateDecryptor(const std::string& key_system,
-                                             media::DecryptorClient* client) {
-  if (key_system == kClearKeyKeySystem)
-    return scoped_ptr<media::Decryptor>(new media::AesDecryptor(client));
-  return scoped_ptr<media::Decryptor>();
+bool CanUseAesDecryptor(const std::string& key_system) {
+  return key_system == kClearKeyKeySystem;
+}
+
+const char* GetPluginType(const std::string& key_system) {
+  for (size_t i = 0; i < arraysize(key_system_to_plugin_type_mapping); ++i) {
+    if (key_system_to_plugin_type_mapping[i].key_system == key_system)
+      return key_system_to_plugin_type_mapping[i].plugin_type;
+  }
+
+  return NULL;
 }
 
 }  // namespace webkit_media