MM-14686 Send all image proxy requests through /api/v4/image (#10775)

* MM-14686 Implement /api/v4/image when proxy is disabled

* MM-14686 Send all image proxy requests through /api/v4/image

* Update unit tests

services/imageproxy/local_test.go

@@ -293,79 +293,3 @@ func TestLocalBackend_GetImageDirect(t *testing.T) {
 		wait <- true
 	})
 }
-
-func TestLocalBackend_GetProxiedImageURL(t *testing.T) {
-	imageURL := "http://www.mattermost.org/wp-content/uploads/2016/03/logoHorizontal.png"
-	proxiedURL := "https://mattermost.example.com/api/v4/image?url=http%3A%2F%2Fwww.mattermost.org%2Fwp-content%2Fuploads%2F2016%2F03%2FlogoHorizontal.png"
-
-	proxy := makeTestLocalProxy()
-
-	for _, test := range []struct {
-		Name     string
-		Input    string
-		Expected string
-	}{
-		{
-			Name:     "should proxy image",
-			Input:    imageURL,
-			Expected: proxiedURL,
-		},
-		{
-			Name:     "should not proxy a relative image",
-			Input:    "/static/logo.png",
-			Expected: "/static/logo.png",
-		},
-		{
-			Name:     "should not proxy an image on the Mattermost server",
-			Input:    "https://mattermost.example.com/static/logo.png",
-			Expected: "https://mattermost.example.com/static/logo.png",
-		},
-		{
-			Name:     "should not proxy an image that has already been proxied",
-			Input:    proxiedURL,
-			Expected: proxiedURL,
-		},
-	} {
-		t.Run(test.Name, func(t *testing.T) {
-			assert.Equal(t, test.Expected, proxy.GetProxiedImageURL(test.Input))
-		})
-	}
-}
-
-func TestLocalBackend_GetUnproxiedImageURL(t *testing.T) {
-	imageURL := "http://www.mattermost.org/wp-content/uploads/2016/03/logoHorizontal.png"
-	proxiedURL := "https://mattermost.example.com/api/v4/image?url=http%3A%2F%2Fwww.mattermost.org%2Fwp-content%2Fuploads%2F2016%2F03%2FlogoHorizontal.png"
-
-	proxy := makeTestLocalProxy()
-
-	for _, test := range []struct {
-		Name     string
-		Input    string
-		Expected string
-	}{
-		{
-			Name:     "should remove proxy",
-			Input:    proxiedURL,
-			Expected: imageURL,
-		},
-		{
-			Name:     "should not remove proxy from a relative image",
-			Input:    "/static/logo.png",
-			Expected: "/static/logo.png",
-		},
-		{
-			Name:     "should not remove proxy from an image on the Mattermost server",
-			Input:    "https://mattermost.example.com/static/logo.png",
-			Expected: "https://mattermost.example.com/static/logo.png",
-		},
-		{
-			Name:     "should not remove proxy from a non-proxied image",
-			Input:    imageURL,
-			Expected: imageURL,
-		},
-	} {
-		t.Run(test.Name, func(t *testing.T) {
-			assert.Equal(t, test.Expected, proxy.GetUnproxiedImageURL(test.Input))
-		})
-	}
-}