exo: Recreate Surface resources on context lost.

components/exo/buffer.cc

Index: components/exo/buffer.cc
diff --git a/components/exo/buffer.cc b/components/exo/buffer.cc
index 5b02cc3c130e4ffff31c1659992b56af080061a7..442d6fbaed21a0724d288c9b8d9de384131f464d 100644
--- a/components/exo/buffer.cc
+++ b/components/exo/buffer.cc
@@ -371,7 +371,9 @@ Buffer::~Buffer() {}
 std::unique_ptr<cc::SingleReleaseCallback> Buffer::ProduceTextureMailbox(
     cc::TextureMailbox* texture_mailbox,
     bool secure_output_only,
-    bool client_usage) {
+    bool client_usage,
+    base::Closure* detach_callback) {
+  DCHECK(detach_callback->is_null());
   // Non-client usage can only be allowed when the client is not allowed to
   // use the buffer. If the buffer has been released to the client then it
   // can no longer be used as the client might be writing to it.
@@ -411,6 +413,11 @@ std::unique_ptr<cc::SingleReleaseCallback> Buffer::ProduceTextureMailbox(
     return nullptr;
   }
 
+  // Add a callback to ensure this buffer isn't released while it's attached
+  // to a surface.
+  use_count_++;
+  *detach_callback = base::Bind(&Buffer::Release, AsWeakPtr());
+
   // Create a new image texture for |gpu_memory_buffer_| with |texture_target_|
   // if one doesn't already exist. The contents of this buffer are copied to
   // |texture| using a call to CopyTexImage.