Simplify the transport dib situation across our various platforms, as a

ui/surface/transport_dib_posix.cc

Index: ui/surface/transport_dib_posix.cc
===================================================================
--- ui/surface/transport_dib_posix.cc	(revision 192091)
+++ ui/surface/transport_dib_posix.cc	(working copy)
@@ -4,6 +4,10 @@
 
 #include "ui/surface/transport_dib.h"
 
+// Desktop GTK Linux builds use the old-style SYSV SHM based DIBs.
+// Linux Aura and Chrome OS do too. This will change very soon.
+#if !defined(TOOLKIT_GTK) && !(defined(OS_LINUX) && defined(USE_AURA))
+
 #include <sys/stat.h>
 #include <unistd.h>
 
@@ -57,7 +61,11 @@
 
 // static
 bool TransportDIB::is_valid_id(Id id) {
+#if defined(OS_ANDROID)
+  return is_valid_handle(id);
+#else
   return id != 0;
+#endif
 }
 
 skia::PlatformCanvas* TransportDIB::GetPlatformCanvas(int w, int h) {
@@ -71,6 +79,11 @@
 bool TransportDIB::Map() {
   if (!is_valid_handle(handle()))
     return false;
+#if defined(OS_ANDROID)
+  if (!shared_memory_.Map(0))
+    return false;
+  size_ = shared_memory_.mapped_size();
+#else
   if (memory())
     return true;
 
@@ -81,6 +94,7 @@
   }
 
   size_ = st.st_size;
+#endif
   return true;
 }
 
@@ -89,9 +103,16 @@
 }
 
 TransportDIB::Id TransportDIB::id() const {
+#if defined(OS_ANDROID)
+  return handle();
+#else
   return shared_memory_.id();
+#endif
 }
 
 TransportDIB::Handle TransportDIB::handle() const {
   return shared_memory_.handle();
 }
+
+#endif  // !defined(TOOLKIT_GTK) && !(defined(OS_LINUX) && defined(USE_AURA))
+