Perfetto: clean up PERFETTO_EMBEDDER_BUILD

- rename most uses of PERFETTO_CHROMIUM_BUILD to
  PERFETTO_EMBEDDER_BUILD. All the existing use cases should
  be used by any embedder, not just chromium.
- Cleans up the definition of PERFETTO_BUILD_WITH_ANDROID. Instead
  of defining on a per-target basis, define in the global
  default_config, together with the rest.

Bug: chromium:921584
Change-Id: I93b0b2843080ca04cbeff0567d538a79550b716b
diff --git a/src/base/watchdog_posix.cc b/src/base/watchdog_posix.cc
index abd57d7..dd68455 100644
--- a/src/base/watchdog_posix.cc
+++ b/src/base/watchdog_posix.cc
@@ -38,8 +38,8 @@
 #include "perfetto/base/scoped_file.h"
 #include "perfetto/base/thread_utils.h"
 
-#if PERFETTO_BUILDFLAG(PERFETTO_CHROMIUM_BUILD)
-#error perfetto::base::Watchdog should not be used in Chromium
+#if PERFETTO_BUILDFLAG(PERFETTO_EMBEDDER_BUILD)
+#error perfetto::base::Watchdog should not be used in Chromium or embedders
 #endif
 
 namespace perfetto {