tools/gn: Fix more "propogated" typos.

tools/gn/builder_unittest.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "testing/gtest/include/gtest/gtest.h"
 #include "tools/gn/builder.h"
 #include "tools/gn/loader.h"
 #include "tools/gn/target.h"
 #include "tools/gn/test_with_scope.h"
 #include "tools/gn/toolchain.h"
@@ skipping 156 matching lines @@
 
   EXPECT_TRUE(a_record->unresolved_deps().empty());
   EXPECT_TRUE(b_record->unresolved_deps().empty());
   EXPECT_TRUE(c_record->unresolved_deps().empty());
 
   EXPECT_TRUE(a_record->waiting_on_resolution().empty());
   EXPECT_TRUE(b_record->waiting_on_resolution().empty());
   EXPECT_TRUE(c_record->waiting_on_resolution().empty());
 }
 
-// Tests that the should generate bit is set and propogated properly.
+// Tests that the "should generate" flag is set and propagated properly.
 TEST_F(BuilderTest, ShouldGenerate) {
   DefineToolchain();
 
   // Define a secondary toolchain.
   Settings settings2(&build_settings_, "secondary/");
   Label toolchain_label2(SourceDir("//tc/"), "secondary");
   settings2.set_toolchain_label(toolchain_label2);
   Toolchain* tc2 = new Toolchain(&settings2, toolchain_label2);
   TestWithScope::SetupToolchain(tc2);
   builder_->ItemDefined(scoped_ptr<Item>(tc2));
@@ skipping 21 matching lines @@
   a->set_output_type(Target::EXECUTABLE);
   builder_->ItemDefined(scoped_ptr<Item>(a));
 
   // A should have the generate bit set since it's in the default toolchain.
   BuilderRecord* a_record = builder_->GetRecord(a_label);
   EXPECT_TRUE(a_record->should_generate());
 
   // It should have gotten pushed to B.
   EXPECT_TRUE(b_record->should_generate());
 }