Add GN variables for controlling header checking.

tools/gn/binary_target_generator.cc

Index: tools/gn/binary_target_generator.cc
diff --git a/tools/gn/binary_target_generator.cc b/tools/gn/binary_target_generator.cc
index 22a5ea633b28f48beac5a9173c7d190216bb2103..b11a529dc0ff0a6baf570c00133a98e3d3d7ab10 100644
--- a/tools/gn/binary_target_generator.cc
+++ b/tools/gn/binary_target_generator.cc
@@ -6,7 +6,9 @@
 
 #include "tools/gn/config_values_generator.h"
 #include "tools/gn/err.h"
+#include "tools/gn/functions.h"
 #include "tools/gn/scope.h"
+#include "tools/gn/value_extractors.h"
 #include "tools/gn/variables.h"
 
 BinaryTargetGenerator::BinaryTargetGenerator(
@@ -41,6 +43,10 @@ void BinaryTargetGenerator::DoRun() {
   if (err_->has_error())
     return;
 
+  FillCheckIncludes();
+  if (err_->has_error())
+    return;
+
   FillInputs();
   if (err_->has_error())
     return;
@@ -49,6 +55,10 @@ void BinaryTargetGenerator::DoRun() {
   if (err_->has_error())
     return;
 
+  FillAllowCircularIncludesFrom();
+  if (err_->has_error())
+    return;
+
   // Config values (compiler flags, etc.) set directly on this target.
   ConfigValuesGenerator gen(&target_->config_values(), scope_,
                             scope_->GetSourceDir(), err_);
@@ -57,6 +67,15 @@ void BinaryTargetGenerator::DoRun() {
     return;
 }
 
+void BinaryTargetGenerator::FillCheckIncludes() {
+  const Value* value = scope_->GetValue(variables::kCheckIncludes, true);
+  if (!value)
+    return;
+  if (!value->VerifyTypeIs(Value::BOOLEAN, err_))
+    return;
+  target_->set_check_includes(value->boolean_value());
+}
+
 void BinaryTargetGenerator::FillOutputName() {
   const Value* value = scope_->GetValue(variables::kOutputName, true);
   if (!value)
@@ -74,3 +93,40 @@ void BinaryTargetGenerator::FillOutputExtension() {
     return;
   target_->set_output_extension(value->string_value());
 }
+
+void BinaryTargetGenerator::FillAllowCircularIncludesFrom() {
+  const Value* value = scope_->GetValue(
+      variables::kAllowCircularIncludesFrom, true);
+  if (!value)
+    return;
+
+  UniqueVector<Label> circular;
+  ExtractListOfUniqueLabels(*value, scope_->GetSourceDir(),
+                            ToolchainLabelForScope(scope_), &circular, err_);
+  if (err_->has_error())
+    return;
+
+  // Validate that all circular includes entries are in the deps.
+  const LabelTargetVector& deps = target_->deps();
+  for (size_t circular_i = 0; circular_i < circular.size(); circular_i++) {
+    bool found_dep = false;
+    for (size_t dep_i = 0; dep_i < deps.size(); dep_i++) {
+      if (deps[dep_i].label == circular[circular_i]) {
+        found_dep = true;
+        break;
+      }
+    }
+    if (!found_dep) {
+      *err_ = Err(*value, "Label not in deps.",
+          "The label \"" + circular[circular_i].GetUserVisibleName(false) +
+          "\"\nwas not in the deps of this target. "
+          "allow_circular_includes_from only allows\ntargets present in the "
+          "deps.");
+      return;
+    }
+  }
+
+  // Add to the set.
+  for (size_t i = 0; i < circular.size(); i++)
+    target_->allow_circular_includes_from().insert(circular[i]);
+}