Bug 1526322 - Ensure GeckoWebExecutor doesn't clobber the Content-Type header. r=csadilek

Differential Revision: https://phabricator.services.mozilla.com/D19506

--HG--
extra : moz-landing-system : lando

mobile/android/geckoview/src/androidTest/java/org/mozilla/geckoview/test/WebExecutorTest.kt

@@ -107,6 +107,7 @@ class WebExecutorTest {
                 .addHeader("Header2", "Value1")
                 .addHeader("Header2", "Value2")
                 .referrer(referrer)
+                .header("Content-Type", "text/plain")
                 .body(bodyString.toDirectByteBuffer())
                 .build()
 
@@ -121,6 +122,7 @@ class WebExecutorTest {
         assertThat("Method should match", body.getString("method"), equalTo("POST"))
         assertThat("Headers should match", body.getJSONObject("headers").getString("Header1"), equalTo("Value"))
         assertThat("Headers should match", body.getJSONObject("headers").getString("Header2"), equalTo("Value1, Value2"))
+        assertThat("Headers should match", body.getJSONObject("headers").getString("Content-Type"), equalTo("text/plain"))
         assertThat("Referrer should match", body.getJSONObject("headers").getString("Referer"), equalTo(referrer))
         assertThat("Data should match", body.getString("data"), equalTo(bodyString));
     }

widget/android/WebExecutorSupport.cpp

@@ -362,14 +362,19 @@ nsresult WebExecutorSupport::CreateStreamLoader(
   // Headers
   const auto keys = reqBase->GetHeaderKeys();
   const auto values = reqBase->GetHeaderValues();
+  auto contentType = EmptyCString();
   for (size_t i = 0; i < keys->Length(); i++) {
-    const auto key = jni::String::LocalRef(keys->GetElement(i));
-    const auto value = jni::String::LocalRef(values->GetElement(i));
+    const auto key = jni::String::LocalRef(keys->GetElement(i))->ToCString();
+    const auto value =
+        jni::String::LocalRef(values->GetElement(i))->ToCString();
+
+    if (key.LowerCaseEqualsASCII("content-type")) {
+      contentType = value;
+    }
 
     // We clobber any duplicate keys here because we've already merged them
     // in the upstream WebRequest.
-    rv = httpChannel->SetRequestHeader(key->ToCString(), value->ToCString(),
-                                       false /* merge */);
+    rv = httpChannel->SetRequestHeader(key, value, false /* merge */);
     NS_ENSURE_SUCCESS(rv, rv);
   }
 
@@ -382,7 +387,7 @@ nsresult WebExecutorSupport::CreateStreamLoader(
     NS_ENSURE_SUCCESS(rv, rv);
 
     rv = uploadChannel->ExplicitSetUploadStream(
-        stream, EmptyCString(), -1, aRequest->Method()->ToCString(), false);
+        stream, contentType, -1, aRequest->Method()->ToCString(), false);
     NS_ENSURE_SUCCESS(rv, rv);
   }