Add texture compression interface and ETC1 encoder.

cc/BUILD.gn

Index: cc/BUILD.gn
diff --git a/cc/BUILD.gn b/cc/BUILD.gn
index bd8bfdd43d2f337fd9f3465cf683418faf7f7c41..29182fdfe9ae8ded20f358266f1e0da1c44b3d13 100644
--- a/cc/BUILD.gn
+++ b/cc/BUILD.gn
@@ -425,6 +425,10 @@ component("cc") {
     "resources/software_rasterizer.h",
     "resources/task_graph_runner.cc",
     "resources/task_graph_runner.h",
+    "resources/texture_compress/texture_compressor.cc",
+    "resources/texture_compress/texture_compressor.h",
+    "resources/texture_compress/texture_compressor_etc1.cc",
+    "resources/texture_compress/texture_compressor_etc1.h",
     "resources/texture_mailbox.cc",
     "resources/texture_mailbox.h",
     "resources/texture_mailbox_deleter.cc",
@@ -876,6 +880,7 @@ test("cc_perftests") {
     "resources/picture_layer_tiling_perftest.cc",
     "resources/picture_pile_impl_perftest.cc",
     "resources/task_graph_runner_perftest.cc",
+    "resources/texture_compress/texture_compressor_perftest.cc",
     "resources/tile_manager_perftest.cc",
     "resources/tile_task_worker_pool_perftest.cc",
     "test/cc_test_suite.cc",