platform2: Move Error class from Buffet to libchromeos

Moved buffet::Error class and related facilities to
libchromeos and changed the namespace to 'chromeos::'.
Updated a bunch of code to include the header files
from the new location and referring to the new
namespace.

BUG=chromium:403604
TEST=USE=buffet ./build_packages
     FEATURES=test emerge-link libchromeos
     USE=buffet FEATURES=test emerge-link platform2

Change-Id: I0b5b37ccd7ee3b7be9467ebfae5d172d9b057cf6
Reviewed-on: https://chromium-review.googlesource.com/212525
Tested-by: Alex Vakulenko <avakulenko@chromium.org>
Reviewed-by: Christopher Wiley <wiley@chromium.org>
Commit-Queue: Alex Vakulenko <avakulenko@chromium.org>
diff --git a/buffet/commands/command_instance_unittest.cc b/buffet/commands/command_instance_unittest.cc
index 3f81016..ace0738 100644
--- a/buffet/commands/command_instance_unittest.cc
+++ b/buffet/commands/command_instance_unittest.cc
@@ -104,7 +104,7 @@
 
 TEST_F(CommandInstanceTest, FromJson_NotObject) {
   auto json = CreateValue("'string'");
-  buffet::ErrorPtr error;
+  chromeos::ErrorPtr error;
   auto instance = buffet::CommandInstance::FromJson(json.get(), dict_, &error);
   EXPECT_EQ(nullptr, instance.get());
   EXPECT_EQ("json_object_expected", error->GetCode());
@@ -113,7 +113,7 @@
 
 TEST_F(CommandInstanceTest, FromJson_NameMissing) {
   auto json = CreateDictionaryValue("{'param': 'value'}");
-  buffet::ErrorPtr error;
+  chromeos::ErrorPtr error;
   auto instance = buffet::CommandInstance::FromJson(json.get(), dict_, &error);
   EXPECT_EQ(nullptr, instance.get());
   EXPECT_EQ("parameter_missing", error->GetCode());
@@ -122,7 +122,7 @@
 
 TEST_F(CommandInstanceTest, FromJson_UnknownCommand) {
   auto json = CreateDictionaryValue("{'name': 'robot.scream'}");
-  buffet::ErrorPtr error;
+  chromeos::ErrorPtr error;
   auto instance = buffet::CommandInstance::FromJson(json.get(), dict_, &error);
   EXPECT_EQ(nullptr, instance.get());
   EXPECT_EQ("invalid_command_name", error->GetCode());
@@ -134,7 +134,7 @@
     'name': 'robot.speak',
     'parameters': 'hello'
   })");
-  buffet::ErrorPtr error;
+  chromeos::ErrorPtr error;
   auto instance = buffet::CommandInstance::FromJson(json.get(), dict_, &error);
   EXPECT_EQ(nullptr, instance.get());
   auto inner = error->GetInnerError();
@@ -152,7 +152,7 @@
       'volume': 20
     }
   })");
-  buffet::ErrorPtr error;
+  chromeos::ErrorPtr error;
   auto instance = buffet::CommandInstance::FromJson(json.get(), dict_, &error);
   EXPECT_EQ(nullptr, instance.get());
   auto first = error->GetFirstError();