Add Widevine CDM support (issue #1631)

- Windows/Mac: Use `--enable-widevine-cdm` command-line flag to
  enable download of CDM binaries via the component updater.
- Linux: Use `--widevide-cdm-path` and `--widevine-cdm-version`
  command-line flags to load CDM binaries that already exist on
  the system.
- A cache-path value is usually required when CDM is enabled.

libcef/common/cef_messages.h

@@ -230,6 +230,20 @@ IPC_SYNC_MESSAGE_CONTROL4_1(CefViewHostMsg_GetPluginInfo,
                             std::string /* mime_type */,
                             CefViewHostMsg_GetPluginInfo_Output /* output */)
 
+// Returns whether any internal plugin supporting |mime_type| is registered and
+// enabled. Does not determine whether the plugin can actually be instantiated
+// (e.g. whether it has all its dependencies).
+// When the returned *|is_available| is true, |additional_param_names| and
+// |additional_param_values| contain the name-value pairs, if any, specified
+// for the *first* non-disabled plugin found that is registered for |mime_type|.
+// Based on ChromeViewHostMsg_IsInternalPluginAvailableForMimeType.
+IPC_SYNC_MESSAGE_CONTROL1_3(
+    CefViewHostMsg_IsInternalPluginAvailableForMimeType,
+    std::string /* mime_type */,
+    bool /* is_available */,
+    std::vector<base::string16> /* additional_param_names */,
+    std::vector<base::string16> /* additional_param_values */)
+
 // Sent when a frame is identified for the first time.
 IPC_MESSAGE_ROUTED3(CefHostMsg_FrameIdentified,
                     int64 /* frame_id */,

libcef/common/cef_switches.cc

@@ -107,4 +107,13 @@ const char kDisablePdfExtension[]         = "disable-pdf-extension";
 // upcoming version of Chromium.
 const char kEnableNPAPI[]                 = "enable-npapi";
 
+// Enable Widevine CDM.
+const char kEnableWidevineCdm[]           = "enable-widevine-cdm";
+
+// Path to Widevine CDM binaries.
+const char kWidevineCdmPath[]             = "widevine-cdm-path";
+
+// Widevine CDM version.
+const char kWidevineCdmVersion[]          = "widevine-cdm-version";
+
 }  // namespace switches

libcef/common/cef_switches.h

@@ -45,6 +45,9 @@ extern const char kEnableSystemFlash[];
 extern const char kDisableScrollBounce[];
 extern const char kDisablePdfExtension[];
 extern const char kEnableNPAPI[];
+extern const char kEnableWidevineCdm[];
+extern const char kWidevineCdmPath[];
+extern const char kWidevineCdmVersion[];
 
 }  // namespace switches
 

libcef/common/content_client.cc

@@ -34,6 +34,14 @@
 #include "ppapi/shared_impl/ppapi_permissions.h"
 #include "ui/base/resource/resource_bundle.h"
 
+#include "widevine_cdm_version.h"  // In SHARED_INTERMEDIATE_DIR.
+
+// The following must be after widevine_cdm_version.h.
+#if defined(WIDEVINE_CDM_AVAILABLE) && defined(ENABLE_PEPPER_CDMS) && \
+    !defined(WIDEVINE_CDM_IS_COMPONENT)
+#include "chrome/common/widevine_cdm_constants.h"
+#endif
+
 namespace {
 
 CefContentClient* g_content_client = NULL;
@@ -171,6 +179,68 @@ bool GetSystemPepperFlash(content::PepperPluginInfo* plugin) {
   return true;
 }
 
+void AddWidevineCdmFromCommandLine(
+    std::vector<content::PepperPluginInfo>* plugins) {
+#if defined(WIDEVINE_CDM_AVAILABLE) && defined(ENABLE_PEPPER_CDMS) && \
+    !defined(WIDEVINE_CDM_IS_COMPONENT)
+  static bool skip_widevine_cdm_file_check = false;
+
+  base::FilePath widevine_cdm_path =
+      base::CommandLine::ForCurrentProcess()->GetSwitchValuePath(
+          switches::kWidevineCdmPath);
+  if (!widevine_cdm_path.empty()) {
+    widevine_cdm_path =
+        widevine_cdm_path.AppendASCII(kWidevineCdmAdapterFileName);
+  }
+
+  // Also get the version from the command-line. Should be something like
+  // 1.4.8.824.
+  const std::string& widevine_cdm_version =
+      base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
+          switches::kWidevineCdmVersion);
+
+  if (!widevine_cdm_path.empty() && !widevine_cdm_version.empty()) {
+    if (skip_widevine_cdm_file_check || base::PathExists(widevine_cdm_path)) {
+      content::PepperPluginInfo widevine_cdm;
+      widevine_cdm.is_out_of_process = true;
+      widevine_cdm.path = widevine_cdm_path;
+      widevine_cdm.name = kWidevineCdmDisplayName;
+      widevine_cdm.description = kWidevineCdmDescription +
+                                 std::string(" (version: ") +
+                                 widevine_cdm_version + ")";
+      widevine_cdm.version = widevine_cdm_version;
+      content::WebPluginMimeType widevine_cdm_mime_type(
+          kWidevineCdmPluginMimeType,
+          kWidevineCdmPluginExtension,
+          kWidevineCdmPluginMimeTypeDescription);
+
+      // Add the supported codecs as if they came from the component manifest.
+      std::vector<std::string> codecs;
+      codecs.push_back(kCdmSupportedCodecVorbis);
+      codecs.push_back(kCdmSupportedCodecVp8);
+      codecs.push_back(kCdmSupportedCodecVp9);
+#if defined(USE_PROPRIETARY_CODECS)
+      codecs.push_back(kCdmSupportedCodecAac);
+      codecs.push_back(kCdmSupportedCodecAvc1);
+#endif  // defined(USE_PROPRIETARY_CODECS)
+      std::string codec_string = base::JoinString(
+          codecs, std::string(1, kCdmSupportedCodecsValueDelimiter));
+      widevine_cdm_mime_type.additional_param_names.push_back(
+          base::ASCIIToUTF16(kCdmSupportedCodecsParamName));
+      widevine_cdm_mime_type.additional_param_values.push_back(
+          base::ASCIIToUTF16(codec_string));
+
+      widevine_cdm.mime_types.push_back(widevine_cdm_mime_type);
+      widevine_cdm.permissions = kWidevineCdmPluginPermissions;
+      plugins->push_back(widevine_cdm);
+
+      skip_widevine_cdm_file_check = true;
+    }
+  }
+#endif  // defined(WIDEVINE_CDM_AVAILABLE) && defined(ENABLE_PEPPER_CDMS) &&
+        // !defined(WIDEVINE_CDM_IS_COMPONENT)
+}
+
 }  // namespace
 
 const char CefContentClient::kPDFPluginPath[] = "internal-pdf-viewer";
@@ -197,6 +267,7 @@ void CefContentClient::AddPepperPlugins(
     std::vector<content::PepperPluginInfo>* plugins) {
   ComputeBuiltInPlugins(plugins);
   AddPepperFlashFromCommandLine(plugins);
+  AddWidevineCdmFromCommandLine(plugins);
 
   content::PepperPluginInfo plugin;
   if (GetSystemPepperFlash(&plugin))

libcef/common/main_delegate.cc

@@ -26,6 +26,7 @@
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/chrome_switches.h"
+#include "chrome/common/widevine_cdm_constants.h"
 #include "content/public/browser/browser_main_runner.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/common/content_switches.h"
@@ -36,6 +37,8 @@
 #include "ui/base/ui_base_paths.h"
 #include "ui/base/ui_base_switches.h"
 
+#include "widevine_cdm_version.h"  // In SHARED_INTERMEDIATE_DIR.
+
 #include "ipc/ipc_message.h"  // For IPC_MESSAGE_LOG_ENABLED.
 
 #if defined(IPC_MESSAGE_LOG_ENABLED)
@@ -525,6 +528,18 @@ void CefMainDelegate::PreSandboxStartup() {
         user_data_path.AppendASCII("Dictionaries"),
         false,  // May not be an absolute path.
         true);  // Create if necessary.
+
+#if defined(WIDEVINE_CDM_AVAILABLE) && defined(ENABLE_PEPPER_CDMS)
+    const base::FilePath& widevine_plugin_path = GetResourcesFilePath();
+    PathService::Override(chrome::FILE_WIDEVINE_CDM_ADAPTER,
+                          widevine_plugin_path.AppendASCII(
+                              kWidevineCdmAdapterFileName));
+#if defined(WIDEVINE_CDM_IS_COMPONENT)
+    PathService::Override(chrome::DIR_COMPONENT_WIDEVINE_CDM,
+                          user_data_path.Append(kWidevineCdmBaseDirectory));
+#endif  // defined(WIDEVINE_CDM_IS_COMPONENT)
+#endif  // defined(WIDEVINE_CDM_AVAILABLE) && defined(ENABLE_PEPPER_CDMS)
+
   }
 
   if (command_line->HasSwitch(switches::kDisablePackLoading))