wire: give wire.Bind access to the arguments to the injector function (google/go-cloud#715)

internal/wire/testdata/BindInjectorArg/want/program_out.txt

@@ -0,0 +1 @@
+hello

internal/wire/testdata/BindInjectorArg/want/wire_errs.txt

@@ -1 +0,0 @@
-example.com/foo/wire.go:x:y: no binding for *example.com/foo.Foo

internal/wire/testdata/BindInjectorArg/want/wire_gen.go

@@ -0,0 +1,13 @@
+// Code generated by Wire. DO NOT EDIT.
+
+//go:generate wire
+//+build !wireinject
+
+package main
+
+// Injectors from wire.go:
+
+func inject(foo *Foo) *Bar {
+	bar := NewBar(foo)
+	return bar
+}

internal/wire/testdata/InjectInputConflict/want/wire_errs.txt

@@ -1 +1,6 @@
-example.com/foo/wire.go:x:y: inject injectBar: input of example.com/foo.Foo conflicts with provider provideFoo at example.com/foo/foo.go:x:y
+example.com/foo/wire.go:x:y: wire.Build has multiple bindings for example.com/foo.Foo
+current:
+<- provider "provideFoo" (example.com/foo/foo.go:x:y)
+<- provider set "Set" (example.com/foo/foo.go:x:y)
+previous:
+<- argument foo to injector function injectBar (example.com/foo/wire.go:x:y)

internal/wire/testdata/InvalidInjector/foo/wire.go

@@ -22,7 +22,7 @@ import (
 
 func injectFoo() Foo {
 	// This non-call statement makes this an invalid injector.
-	 _ = 42
+	_ = 42
 	panic(wire.Build(provideFoo))
 }
 

internal/wire/testdata/MultipleArgsSameType/want/wire_errs.txt

@@ -1 +1,5 @@
-example.com/foo/wire.go:x:y: inject inject: multiple inputs of the same type string
+example.com/foo/wire.go:x:y: wire.Build has multiple bindings for string
+current:
+<- argument b to injector function inject (example.com/foo/wire.go:x:y)
+previous:
+<- argument a to injector function inject (example.com/foo/wire.go:x:y)

internal/wire/testdata/UnexportedStruct/bar/bar.go

@@ -17,5 +17,3 @@ package bar
 var foo struct {
 	X int
 }
-
-