Disable Blink assertions on Chromecast device builds

third_party/WebKit/Source/config.gni

Index: third_party/WebKit/Source/config.gni
diff --git a/third_party/WebKit/Source/config.gni b/third_party/WebKit/Source/config.gni
index 80893ce8ffb8ff85cdd008caf58b877db6186a6c..45d5c8365786a7e17b3a4890e9634911b883ae75 100644
--- a/third_party/WebKit/Source/config.gni
+++ b/third_party/WebKit/Source/config.gni
@@ -19,6 +19,10 @@ declare_args() {
   # Set to true to enable the clang plugin that checks the usage of the Blink
   # garbage-collection infrastructure during compilation.
   blink_gc_plugin = true
+
+  # If true, force blink asserts to be off in a release build.  When false,
+  # blink asserts in release build may be controlled by DCHECK_ALWAYS_ON.
+  blink_asserts_off_in_release = false
 }
 
 # Whether Android ARM or x86 build uses OpenMAX DL FFT. Currently only
@@ -90,6 +94,9 @@ if (use_default_render_theme) {
 if (enable_oilpan) {
   feature_defines_list += [ "ENABLE_OILPAN=1" ]
 }
+if (blink_asserts_off_in_release && !is_debug) {
+  feature_defines_list += [ "ENABLE_ASSERT=0" ]
+}
 
 # feature_defines_string -------------------------------------------------------