Move ChromeOS/Android checking for legacy protocol to build files.

mojo/edk/system/channel.cc

Index: mojo/edk/system/channel.cc
diff --git a/mojo/edk/system/channel.cc b/mojo/edk/system/channel.cc
index ee9faa23ff8e771b86a23bafbffbb20433cdaa78..ac97fbbf29c68463d9f9d3cde643b10241f13599 100644
--- a/mojo/edk/system/channel.cc
+++ b/mojo/edk/system/channel.cc
@@ -29,7 +29,7 @@ namespace {
 static_assert(sizeof(Channel::Message::Header) % kChannelMessageAlignment == 0,
     "Invalid Header size.");
 
-#if defined(OS_CHROMEOS) || defined(OS_ANDROID)
+#if defined(MOJO_EDK_LEGACY_PROTOCOL)
 static_assert(sizeof(Channel::Message::Header) == 8,
               "Header must be 8 bytes on ChromeOS and Android");
 #endif
@@ -67,7 +67,7 @@ Channel::Message::Message(size_t payload_size,
                          (extra_header_size % kChannelMessageAlignment);
   }
   DCHECK_EQ(0u, extra_header_size % kChannelMessageAlignment);
-#if defined(OS_CHROMEOS) || defined(OS_ANDROID)
+#if defined(MOJO_EDK_LEGACY_PROTOCOL)
   DCHECK_EQ(0u, extra_header_size);
 #endif
 
@@ -88,7 +88,7 @@ Channel::Message::Message(size_t payload_size,
   DCHECK_LE(sizeof(Header) + extra_header_size,
             std::numeric_limits<uint16_t>::max());
   header_->message_type = message_type;
-#if defined(OS_CHROMEOS) || defined(OS_ANDROID)
+#if defined(MOJO_EDK_LEGACY_PROTOCOL)
   header_->num_handles = static_cast<uint16_t>(max_handles);
 #else
   header_->num_header_bytes =
@@ -192,7 +192,7 @@ Channel::MessagePtr Channel::Message::Deserialize(const void* data,
 }
 
 size_t Channel::Message::payload_size() const {
-#if defined(OS_CHROMEOS) || defined(OS_ANDROID)
+#if defined(MOJO_EDK_LEGACY_PROTOCOL)
   return header_->num_bytes - sizeof(Header);
 #else
   return size_ - header_->num_header_bytes;
@@ -215,7 +215,7 @@ bool Channel::Message::has_mach_ports() const {
 #endif
 
 void Channel::Message::SetHandles(ScopedPlatformHandleVectorPtr new_handles) {
-#if defined(OS_CHROMEOS) || defined(OS_ANDROID)
+#if defined(MOJO_EDK_LEGACY_PROTOCOL)
   // Old semantics for ChromeOS and Android
   if (header_->num_handles == 0) {
     CHECK(!new_handles || new_handles->size() == 0);
@@ -238,7 +238,7 @@ void Channel::Message::SetHandles(ScopedPlatformHandleVectorPtr new_handles) {
   for (size_t i = 0; i < handle_vector_->size(); i++)
     handles_[i].handle = base::win::HandleToUint32((*handle_vector_)[i].handle);
 #endif  // defined(OS_WIN)
-#endif  // defined(OS_CHROMEOS) || defined(OS_ANDROID)
+#endif  // defined(MOJO_EDK_LEGACY_PROTOCOL)
 
 #if defined(OS_MACOSX) && !defined(OS_IOS)
   size_t mach_port_index = 0;
@@ -506,7 +506,7 @@ bool Channel::OnReadComplete(size_t bytes_read, size_t *next_read_size_hint) {
       return true;
     }
 
-#if defined(OS_CHROMEOS) || defined(OS_ANDROID)
+#if defined(MOJO_EDK_LEGACY_PROTOCOL)
     size_t extra_header_size = 0;
     const void* extra_header = nullptr;
     size_t payload_size = header->num_bytes - sizeof(Message::Header);
@@ -527,7 +527,7 @@ bool Channel::OnReadComplete(size_t bytes_read, size_t *next_read_size_hint) {
                            const_cast<char*>(read_buffer_->occupied_bytes()) +
                            header->num_header_bytes)
                      : nullptr;
-#endif  // defined(OS_CHROMEOS) || defined(OS_ANDROID)
+#endif  // defined(MOJO_EDK_LEGACY_PROTOCOL)
 
     ScopedPlatformHandleVectorPtr handles;
     if (header->num_handles > 0) {