Added .gitmodules for dawn and glfw

Change-Id: If75d470e56a6e7775d869fac78081af7b753fa57

.gitmodules

diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..7e7a598
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,6 @@
+[submodule "third_party/dawn"]
+	path = third_party/dawn
+	url = https://dawn.googlesource.com/dawn.git
+[submodule "third_party/glfw"]
+	path = third_party/glfw
+	url = https://chromium.googlesource.com/external/github.com/glfw/glfw

third_party/dawn

diff --git a/third_party/dawn b/third_party/dawn
new file mode 160000
index 0000000..18ac67f
--- /dev/null
+++ b/third_party/dawn
@@ -0,0 +1 @@
+Subproject commit 18ac67fc72dfff47efec97c2a8bcf654a13a9e37

third_party/glfw

diff --git a/third_party/glfw b/third_party/glfw
new file mode 160000
index 0000000..62e175e
--- /dev/null
+++ b/third_party/glfw
@@ -0,0 +1 @@
+Subproject commit 62e175ef9fae75335575964c845a302447c012c7