ShaderModule: Enable the prettier tint diagnostic formatter

Includes code snippits and squiggles of the offending line(s)

Bug: none
Change-Id: If704b5d1118d0246c16f6e729a10d16363a1169b
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/37281
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Auto-Submit: Ben Clayton <bclayton@google.com>
diff --git a/src/dawn_native/ShaderModule.cpp b/src/dawn_native/ShaderModule.cpp
index 3e1f3d9..98cdfa8 100644
--- a/src/dawn_native/ShaderModule.cpp
+++ b/src/dawn_native/ShaderModule.cpp
@@ -179,7 +179,8 @@
 
             tint::reader::wgsl::Parser parser(file);
             if (!parser.Parse()) {
-                errorStream << "Parser: " << parser.error() << std::endl;
+                auto err = tint::diag::Formatter{}.format(parser.diagnostics());
+                errorStream << "Parser: " << err << std::endl;
                 return DAWN_VALIDATION_ERROR(errorStream.str().c_str());
             }
 
@@ -229,7 +230,8 @@
 
             tint::Validator validator;
             if (!validator.Validate(module)) {
-                errorStream << "Validation: " << validator.error() << std::endl;
+                auto err = tint::diag::Formatter{}.format(validator.diagnostics());
+                errorStream << "Validation: " << err << std::endl;
                 return DAWN_VALIDATION_ERROR(errorStream.str().c_str());
             }