provider/aws: Fix launch_config waiting for IAM instance profile

AWS changed their error message, which was being used for detection of
the specific error that indicates we need to wait for IAM propagation.

Behavior is covered by a test now.

Fixes hashicorp#5862

builtin/providers/aws/resource_aws_launch_configuration.go

@@ -7,6 +7,7 @@ import (
 	"encoding/hex"
 	"fmt"
 	"log"
+	"strings"
 	"time"
 
 	"github.com/aws/aws-sdk-go/aws"
@@ -432,7 +433,7 @@ func resourceAwsLaunchConfigurationCreate(d *schema.ResourceData, meta interface
 		_, err := autoscalingconn.CreateLaunchConfiguration(&createLaunchConfigurationOpts)
 		if err != nil {
 			if awsErr, ok := err.(awserr.Error); ok {
-				if awsErr.Message() == "Invalid IamInstanceProfile" {
+				if strings.Contains(awsErr.Message(), "Invalid IamInstanceProfile") {
 					return resource.RetryableError(err)
 				}
 			}

builtin/providers/aws/resource_aws_launch_configuration_test.go

@@ -89,6 +89,24 @@ func TestAccAWSLaunchConfiguration_withSpotPrice(t *testing.T) {
 	})
 }
 
+func TestAccAWSLaunchConfiguration_withIAMProfile(t *testing.T) {
+	var conf autoscaling.LaunchConfiguration
+
+	resource.Test(t, resource.TestCase{
+		PreCheck:     func() { testAccPreCheck(t) },
+		Providers:    testAccProviders,
+		CheckDestroy: testAccCheckAWSLaunchConfigurationDestroy,
+		Steps: []resource.TestStep{
+			resource.TestStep{
+				Config: testAccAWSLaunchConfigurationConfig_withIAMProfile,
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckAWSLaunchConfigurationExists("aws_launch_configuration.bar", &conf),
+				),
+			},
+		},
+	})
+}
+
 func testAccCheckAWSLaunchConfigurationWithEncryption(conf *autoscaling.LaunchConfiguration) resource.TestCheckFunc {
 	return func(s *terraform.State) error {
 		// Map out the block devices by name, which should be unique.
@@ -337,3 +355,35 @@ resource "aws_launch_configuration" "baz" {
 	}
 }
 `
+
+const testAccAWSLaunchConfigurationConfig_withIAMProfile = `
+resource "aws_iam_role" "role" {
+	name  = "TestAccAWSLaunchConfiguration-withIAMProfile"
+  assume_role_policy = <<EOF
+{
+  "Version": "2012-10-17",
+  "Statement": [
+    {
+      "Action": "sts:AssumeRole",
+      "Principal": {
+        "Service": "ec2.amazonaws.com"
+      },
+      "Effect": "Allow",
+      "Sid": ""
+    }
+  ]
+}
+EOF
+}
+
+resource "aws_iam_instance_profile" "profile" {
+	name  = "TestAccAWSLaunchConfiguration-withIAMProfile"
+	roles = ["${aws_iam_role.role.name}"]
+}
+
+resource "aws_launch_configuration" "bar" {
+	image_id             = "ami-5189a661"
+	instance_type        = "t2.nano"
+	iam_instance_profile = "${aws_iam_instance_profile.profile.name}"
+}
+`