Add config option for maxInboundMsgSize

[ajaaym]

For some client we need to set maxInboundMsgSize, right now we are using synth to update code after generation. Can it be added as part of gapic config? Please see this comment

[noahdietz]

@ajaaym We actually ran into a similar with some big query GAPICs last week. What we will do is remove the limits now in order to stop such errors, and we will make it configurable in the future as part of the proto annotation/micro-generator migration. The specific steps:

1. gapic-generator will generate the client options for max call recv & send msg sizes with an unbounded value (-1 makes it limitless) for all languages. This will not be made configurable in the GAPIC config.
2. With the adoption of micro-generators and proto annotations, retry will be configured via a gRPC ServiceConfig JSON file. This proto also contains config for the aforementioned message size options we'd like service owners to toggle. Micro-generators will respect this config, and default to limitless message sizes when absent.

Note: gapic-generator will also support this new config when consuming proto annotations, so it will eventually be configurable for gapic-generator as well.

I am starting work on 1. presently. I will reference this issue in my PR to notify you of its completion.

[noahdietz]

Hm, it seems that for grpc-java, a limitless value of -1 might not be allowed per. I will use your change of Integer.MAX_VALUE for Java's default.

[noahdietz]

Note: #2900 won't take effect until it has been released and clients have been regenerated.

[ajaaym]

@noahdietz Thanks a lot for quick turnaround.