Implement Just-In-Time Flash updates.

chrome/browser/plugins/plugin_info_message_filter.cc

Index: chrome/browser/plugins/plugin_info_message_filter.cc
diff --git a/chrome/browser/plugins/plugin_info_message_filter.cc b/chrome/browser/plugins/plugin_info_message_filter.cc
index 6f6e18fd1c146abba9a960857812b3174e2e28e2..073c284e93a7a6384c1808b9d04a9dd5ae78cb49 100644
--- a/chrome/browser/plugins/plugin_info_message_filter.cc
+++ b/chrome/browser/plugins/plugin_info_message_filter.cc
@@ -10,6 +10,7 @@
 #include <utility>
 
 #include "base/bind.h"
+#include "base/memory/ptr_util.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/threading/thread_task_runner_handle.h"
@@ -24,6 +25,7 @@
 #include "chrome/browser/ui/browser_otr_state.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/common/render_messages.h"
+#include "components/component_updater/component_updater_service.h"
 #include "components/content_settings/core/browser/content_settings_utils.h"
 #include "components/content_settings/core/browser/host_content_settings_map.h"
 #include "components/content_settings/core/browser/plugins_field_trial.h"
@@ -251,32 +253,32 @@ void PluginInfoMessageFilter::PluginsLoaded(
     const GetPluginInfo_Params& params,
     IPC::Message* reply_msg,
     const std::vector<WebPluginInfo>& plugins) {
-  ChromeViewHostMsg_GetPluginInfo_Output output;
+  std::unique_ptr<ChromeViewHostMsg_GetPluginInfo_Output> output(
+      new ChromeViewHostMsg_GetPluginInfo_Output());
   // This also fills in |actual_mime_type|.
   std::unique_ptr<PluginMetadata> plugin_metadata;
   if (context_.FindEnabledPlugin(params.render_frame_id, params.url,
                                  params.top_origin_url, params.mime_type,
-                                 &output.status, &output.plugin,
-                                 &output.actual_mime_type,
+                                 &output->status, &output->plugin,
+                                 &output->actual_mime_type,
                                  &plugin_metadata)) {
-    context_.DecidePluginStatus(params, output.plugin, plugin_metadata.get(),
-                                &output.status);
+    context_.DecidePluginStatus(params, output->plugin, plugin_metadata.get(),
+                                &output->status);
   }
 
-  if (plugin_metadata) {
-    output.group_identifier = plugin_metadata->identifier();
-    output.group_name = plugin_metadata->name();
-  }
-
-  context_.MaybeGrantAccess(output.status, output.plugin.path);
-
-  ChromeViewHostMsg_GetPluginInfo::WriteReplyParams(reply_msg, output);
-  Send(reply_msg);
-  if (output.status !=
-      ChromeViewHostMsg_GetPluginInfo_Status::kNotFound) {
+  if (output->status == ChromeViewHostMsg_GetPluginInfo_Status::kNotFound) {
+    // Check to see if the component updater can fetch an implementation.
+    scoped_refptr<base::SingleThreadTaskRunner> reply_task_runner(
+          base::ThreadTaskRunnerHandle::Get());
     main_thread_task_runner_->PostTask(

[Bernhard Bauer, 2016/07/28 10:25:10]

You could do this with PostTaskAndReply().

[waffles, 2016/07/28 20:06:27]

Hm, I avoided this the first time because (IIUC) it requires me to introduce a
ref-counted struct to hold output and plugin_metadata, and that seemed like it
needlessly complicated the ownership.

I don't mind switching to that approach, but just wanted to check that this was
the intent.

[Bernhard Bauer, 2016/07/29 09:14:24]

No, the callbacks would be exactly the same. The only difference is you wouldn't
have to pass the second callback or the task runner into the first callback.

[waffles, 2016/07/29 21:07:25]

I think I'm still confused about what you mean here - in particular, we don't
pass the second callback here at all; but anyways while looking at this I think
I found a nicer way to express it, so... maybe done? PTAL.

-        FROM_HERE, base::Bind(&ReportMetrics, output.actual_mime_type,
-                              params.url, params.top_origin_url));
+        FROM_HERE,
+        base::Bind(&PluginInfoMessageFilter::FindComponentUpdatePlugin,
+                   this, params,
+                   base::Passed(&output), base::Passed(&plugin_metadata),
+                   reply_msg, reply_task_runner));
+  } else {
+    GetPluginInfoReply(params, std::move(output), std::move(plugin_metadata),
+                       reply_msg);
   }
 }
 
@@ -460,6 +462,57 @@ bool PluginInfoMessageFilter::Context::FindEnabledPlugin(
   return enabled;
 }
 
+void PluginInfoMessageFilter::FindComponentUpdatePlugin(
+    const GetPluginInfo_Params& params,
+    std::unique_ptr<ChromeViewHostMsg_GetPluginInfo_Output> output,
+    std::unique_ptr<PluginMetadata> plugin_metadata,
+    IPC::Message* reply_msg,
+    scoped_refptr<base::SingleThreadTaskRunner> reply_task_runner) {
+  // See if we can fetch the plugin using a component update.
+  component_updater::ComponentInfo cus_plugin_info;
+  if (g_browser_process->component_updater()->GetComponentForMimeType(
+      params.mime_type, &cus_plugin_info)) {
+    output->status =
+        ChromeViewHostMsg_GetPluginInfo_Status::kComponentUpdateRequired;
+    plugin_metadata = base::WrapUnique(new PluginMetadata(

[Bernhard Bauer, 2016/07/28 10:25:10]

You could even use base::MakeUnique<PluginMetadata>() :)

[waffles, 2016/07/28 20:06:27]

Done. (used reset().)

+        cus_plugin_info.id,
+        cus_plugin_info.name,
+        false,
+        GURL(),
+        GURL(),
+        base::ASCIIToUTF16(cus_plugin_info.id),
+        std::string()));
+  }
+  reply_task_runner->PostTask(
+      FROM_HERE,
+      base::Bind(&PluginInfoMessageFilter::GetPluginInfoReply,
+                 this, params, base::Passed(&output),
+                 base::Passed(&plugin_metadata), reply_msg));
+}
+
+void PluginInfoMessageFilter::GetPluginInfoReply(
+    const GetPluginInfo_Params& params,
+    std::unique_ptr<ChromeViewHostMsg_GetPluginInfo_Output> output,
+    std::unique_ptr<PluginMetadata> plugin_metadata,
+    IPC::Message* reply_msg) {
+  if (plugin_metadata) {
+    output->group_identifier = plugin_metadata->identifier();
+    output->group_name = plugin_metadata->name();
+  }
+
+  context_.MaybeGrantAccess(output->status, output->plugin.path);
+
+  ChromeViewHostMsg_GetPluginInfo::WriteReplyParams(reply_msg, *output);
+  Send(reply_msg);
+  if (output->status !=
+      ChromeViewHostMsg_GetPluginInfo_Status::kNotFound) {
+    main_thread_task_runner_->PostTask(
+        FROM_HERE, base::Bind(&ReportMetrics, output->actual_mime_type,
+                              params.url, params.top_origin_url));
+  }
+}
+
+
 void PluginInfoMessageFilter::Context::GetPluginContentSetting(
     const WebPluginInfo& plugin,
     const GURL& policy_url,