tint/utils: Add operator<<() support to vector

Helpful for tests and the like.

Change-Id: I07f8c59af6db4d6a5629dca2dc985398b75eccf9
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/111760
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Ben Clayton <bclayton@google.com>

src/tint/sem/binding_point.h

@@ -18,6 +18,7 @@
 #include <stdint.h>
 
 #include <functional>
+#include <ostream>
 
 #include "src/tint/reflection.h"
 #include "src/tint/utils/hash.h"
@@ -47,6 +48,14 @@ struct BindingPoint {
     inline bool operator!=(const BindingPoint& rhs) const { return !(*this == rhs); }
 };
 
+/// Prints the BindingPoint @p bp to @p o
+/// @param o the std::ostream to write to
+/// @param bp the BindingPoint
+/// @return the std::ostream so calls can be chained
+inline std::ostream& operator<<(std::ostream& o, const BindingPoint& bp) {
+    return o << "[group: " << bp.group << ", binding: " << bp.binding << "]";
+}
+
 }  // namespace tint::sem
 
 namespace std {

src/tint/sem/sampler_texture_pair.h

@@ -17,6 +17,7 @@
 
 #include <cstdint>
 #include <functional>
+#include <ostream>
 
 #include "src/tint/sem/binding_point.h"
 
@@ -43,6 +44,15 @@ struct SamplerTexturePair {
     inline bool operator!=(const SamplerTexturePair& rhs) const { return !(*this == rhs); }
 };
 
+/// Prints the SamplerTexturePair @p stp to @p o
+/// @param o the std::ostream to write to
+/// @param stp the SamplerTexturePair
+/// @return the std::ostream so calls can be chained
+inline std::ostream& operator<<(std::ostream& o, const SamplerTexturePair& stp) {
+    return o << "[sampler: " << stp.sampler_binding_point
+             << ", texture: " << stp.sampler_binding_point << "]";
+}
+
 }  // namespace tint::sem
 
 namespace std {