net: Add out-of-line copy ctors for complex classes.

This patch adds out of line copy constructors for classes that our
clang-plugin considers heavy. This is an effort to enable copy
constructor checks by default.

BUG=436357
[email protected], [email protected], [email protected]

Review URL: https://codereview.chromium.org/1728333003

Cr-Commit-Position: refs/heads/master@{#377976}
diff --git a/net/dns/host_resolver_impl.cc b/net/dns/host_resolver_impl.cc
index 93750ffc..af91b09 100644
--- a/net/dns/host_resolver_impl.cc
+++ b/net/dns/host_resolver_impl.cc
@@ -1854,6 +1854,9 @@
     max_retry_attempts = kDefaultMaxRetryAttempts;
 }
 
+HostResolverImpl::ProcTaskParams::ProcTaskParams(const ProcTaskParams& other) =
+    default;
+
 HostResolverImpl::ProcTaskParams::~ProcTaskParams() {}
 
 HostResolverImpl::HostResolverImpl(const Options& options, NetLog* net_log)