Add CdmService to keep track of CDMs

content/zygote/zygote_main_linux.cc

Index: content/zygote/zygote_main_linux.cc
diff --git a/content/zygote/zygote_main_linux.cc b/content/zygote/zygote_main_linux.cc
index c30e1084a92c6eecaf07417f30c3d5464b9b0f8a..7c0f5c038a6c8b30ab5cf6e89f07d3dcfd267484 100644
--- a/content/zygote/zygote_main_linux.cc
+++ b/content/zygote/zygote_main_linux.cc
@@ -36,6 +36,7 @@
 #include "content/common/sandbox_linux/sandbox_debug_handling_linux.h"
 #include "content/common/sandbox_linux/sandbox_linux.h"
 #include "content/common/zygote_commands_linux.h"
+#include "content/public/common/content_decryption_module_service.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/main_function_params.h"
 #include "content/public/common/sandbox_linux.h"
@@ -318,6 +319,29 @@ void PreloadPepperPlugins() {
 }
 #endif
 
+// Loads any registered Content Decryption Modules but does not initialize
+// them. This is needed by the zygote on Linux to get access to the modules
+// before entering the sandbox.
+void PreloadContentDecryptionModules() {
+  std::vector<std::pair<std::string, base::FilePath>> modules;
+
+  ContentDecryptionModuleService::GetInstance()->GetAllRegisteredModules(
+      &modules);
+  for (const auto& module : modules) {
+    const auto& module_library_path = module.second;
+    if (!module_library_path.empty()) {
+      base::NativeLibraryLoadError error;
+      base::NativeLibrary library =
+          base::LoadNativeLibrary(module_library_path, &error);
+      VLOG_IF(1, !library) << "Unable to load key system "
+                           << module_library_path.value() << " "
+                           << error.ToString();
+
+      (void)library;  // Prevent release-mode warning.
+    }
+  }
+}
+
 // This function triggers the static and lazy construction of objects that need
 // to be created before imposing the sandbox.
 static void ZygotePreSandboxInit() {
@@ -346,6 +370,10 @@ static void ZygotePreSandboxInit() {
 #endif
   SkFontConfigInterface::SetGlobal(
       new FontConfigIPC(GetSandboxFD()))->unref();
+
+  // Ensure access to Content Decryption Modules before the sandbox is
+  // turned on.
+  PreloadContentDecryptionModules();
 }
 
 static bool CreateInitProcessReaper(base::Closure* post_fork_parent_callback) {