Use #include <webgpu/*> instead of #include "dawn/*"

Updates all the includes to (1) note that these are headers from the
include directories via angle braces, and (2) use the headers from the
"webgpu" directory instead of the "dawn" directory. This allows us to
override the headers i.e. in Emscripten case, to point to the correct
header.

Change-Id: Ic4ceaeed7e4379df65a8a159e40d57ad9e1ac290
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/199954
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Loko Kung <lokokung@google.com>
Reviewed-by: Kai Ninomiya <kainino@chromium.org>
diff --git a/docs/quickstart-cmake.md b/docs/quickstart-cmake.md
index 942f30f..1cce6d8 100644
--- a/docs/quickstart-cmake.md
+++ b/docs/quickstart-cmake.md
@@ -62,9 +62,10 @@
 Now, create a `hello_webgpu.cpp` C++ file within the `TestDawn` directory.
 
 ```cpp
+#include <webgpu/webgpu_cpp.h>
+
 #include <cstdlib>
 #include <iostream>
-#include <webgpu/webgpu_cpp.h>
 
 int main(int argc, char *argv[]) {
   wgpu::InstanceDescriptor instanceDescriptor{};