Add rust crate log to third_party.

BUILD.gn

@@ -48,6 +48,7 @@ rust_staticlib("handlers") {
   extern = [
     "$rust_build:libc",
     "$rust_build:url",
+    "$rust_build:log",
   ]
 }
 
@@ -56,6 +57,7 @@ rust_test("handlers_test") {
   extern = [
     "$rust_build:libc",
     "$rust_build:url",
+    "$rust_build:log",
   ]
 }
 

build_extra/rust/BUILD.gn

@@ -55,3 +55,12 @@ rust_component("unicode_bidi") {
 rust_component("unicode_normalization") {
   source_root = "$crates/unicode-normalization/src/lib.rs"
 }
+
+rust_component("log") {
+  source_root = "$crates/log/src/lib.rs"
+  extern = [ ":cfg_if" ]
+}
+
+rust_component("cfg_if") {
+  source_root = "$crates/cfg_if/src/lib.rs"
+}

gclient_config.py

@@ -62,4 +62,11 @@ solutions = [{
     'https://github.com/behnam/rust-unicode-normalization.git@3898e77b110246cb7243bf29b896c58d8975304a',
     'name':
     'rust_crates/unicode-normalization'
+}, {
+    'url': 'https://github.com/rust-lang-nursery/log.git@0.4.2',
+    'name': 'rust_crates/log'
+}, {
+    # Needed for log.
+    'url': 'https://github.com/alexcrichton/cfg-if.git@0.1.4',
+    'name': 'rust_crates/cfg_if'
 }]