Migrated ILBC and ISAC test targets for GN.

Migrated GN targets ilbc_test, isac_api_test,
isac_switch_samprate_test from webrtc/modules/audio_coding/codecs

NOTRY=True
NOPRESUBMIT=True

BUG=webrtc:6191

Review-Url: https://codereview.webrtc.org/2270403002
Cr-Commit-Position: refs/heads/master@{#13953}
diff --git a/webrtc/modules/audio_coding/BUILD.gn b/webrtc/modules/audio_coding/BUILD.gn
index 8918347..2f70fbf 100644
--- a/webrtc/modules/audio_coding/BUILD.gn
+++ b/webrtc/modules/audio_coding/BUILD.gn
@@ -541,6 +541,8 @@
     ":audio_decoder_interface",
     ":audio_encoder_interface",
     ":isac_common",
+    "../..:webrtc_common",
+    "../../base:rtc_base_approved",
     "../../common_audio",
   ]
 }
@@ -1603,6 +1605,70 @@
     ]
   }
 
+  executable("isac_api_test") {
+    testonly = true
+
+    sources = [
+      "codecs/isac/main/test/ReleaseTest-API/ReleaseTest-API.cc",
+      "codecs/isac/main/util/utility.c",
+    ]
+
+    configs += [ "../..:common_config" ]
+    public_configs = [ "../..:common_inherited_config" ]
+
+    deps = [
+      ":isac",
+      "../../base:rtc_base_approved",
+      "//build/config/sanitizers:deps",
+    ]
+
+    include_dirs = [
+      "codecs/isac/main/include",
+      "codecs/isac/main/test",
+      "codecs/isac/main/util",
+    ]
+  }
+
+  executable("isac_switch_samprate_test") {
+    testonly = true
+
+    sources = [
+      "codecs/isac/main/test/SwitchingSampRate/SwitchingSampRate.cc",
+      "codecs/isac/main/util/utility.c",
+    ]
+
+    configs += [ "../..:common_config" ]
+    public_configs = [ "../..:common_inherited_config" ]
+
+    deps = [
+      ":isac",
+      "//build/config/sanitizers:deps",
+    ]
+
+    include_dirs = [
+      "codecs/isac/main/include",
+      "codecs/isac/main/test",
+      "codecs/isac/main/util",
+      "../../common_audio/signal_processing/include",
+    ]
+  }
+
+  executable("ilbc_test") {
+    testonly = true
+
+    sources = [
+      "codecs/ilbc/test/iLBC_test.c",
+    ]
+
+    configs += [ "../..:common_config" ]
+    public_configs = [ "../..:common_inherited_config" ]
+
+    deps = [
+      ":ilbc",
+      "//build/config/sanitizers:deps",
+    ]
+  }
+
   executable("webrtc_opus_fec_test") {
     testonly = true