Reverts "[Fuchsia] only download fuchsia deps when necessary (#51439)" (#51500)

Reverts: #51439
Initiated by: zijiehe-google-com
Reason for reverting: broke dart->flutter roller due to the expected licenses not being included without `download_fuchsia_deps` in `.gclient`.
Original PR Author: zijiehe-google-com

Reviewed By: {zanderso}

This change reverts the following previous change:
This is a quick follow up of #51072 to only download fuchsia deps (via download_fuchsia_deps gclient arg) when necessary. Considering the pr/51072 is very huge, keeping these condition changes in a separate change would be cleaner.

The wiki has been updated already since setting the download_fuchsia_deps gclient arg explicitly won't break the existing workflow. I also mentioned in the wiki that building and running fuchsia needed a linux box (an explicit assertion in the with_envs.py).

Bug: http://b/40935282

[C++, Objective-C, Java style guides]: https://github.com/flutter/engine/blob/main/CONTRIBUTING.md#style

Author: auto-submit[bot]

.ci.yaml

@@ -209,13 +209,6 @@ targets:
     properties:
       release_build: "true"
       config_name: linux_fuchsia
-      # pm in fuchsia-sdk is required when uploading artifacts, so we have to
-      # download the fuchsia-deps in root builder.
-      gclient_variables: >-
-        {
-          "download_android_deps": false,
-          "download_fuchsia_deps": true
-        }
     # Do not remove(https://github.com/flutter/flutter/issues/144644)
     # Scheduler will fail to get the platform
     drone_dimensions:
@@ -311,11 +304,6 @@ targets:
       add_recipes_cq: "true"
       config_name: linux_license
       clobber: "true"
-      # Ensure licenses in fuchsia deps can be correctly processed.
-      gclient_variables: >-
-        {
-          "download_fuchsia_deps": true
-        }
 
   - name: Linux linux_web_engine
     recipe: engine_v2/engine_v2

DEPS

@@ -110,7 +110,9 @@ vars = {
   # Checkout Fuchsia dependencies only on Linux. This is the umbrella flag which
   # controls the behavior of all fuchsia related flags. I.e. any fuchsia related
   # logic or condition may not work if this flag is False.
-  'download_fuchsia_deps': False,
+  # TODO(zijiehe): Make this condition more strict to only download fuchsia
+  # dependencies when necessary: b/40935282
+  'download_fuchsia_deps': 'host_os == "linux"',
   # Downloads the fuchsia SDK as listed in fuchsia_sdk_path var. This variable
   # is currently only used for the Fuchsia LSC process and is not intended for
   # local development.
@@ -1208,7 +1210,7 @@ hooks = [
   {
     'name': 'Download Fuchsia system images',
     'pattern': '.',
-    'condition': 'download_fuchsia_deps and run_fuchsia_emu',
+    'condition': 'run_fuchsia_emu',
     'action': [
       'env',
       'DOWNLOAD_FUCHSIA_SDK={download_fuchsia_sdk}',

ci/builders/linux_fuchsia.json

@@ -5,6 +5,9 @@
                 "device_type=none",
                 "os=Linux"
             ],
+            "gclient_variables": {
+                "download_android_deps": false
+            },
             "gn": [
                 "--fuchsia",
                 "--fuchsia-cpu",
@@ -28,6 +31,7 @@
                 "os=Linux"
             ],
             "gclient_variables": {
+                "download_android_deps": false,
                 "run_fuchsia_emu": true
             },
             "gn": [
@@ -64,6 +68,9 @@
                 "device_type=none",
                 "os=Linux"
             ],
+            "gclient_variables": {
+                "download_android_deps": false
+            },
             "gn": [
                 "--fuchsia",
                 "--fuchsia-cpu",
@@ -87,6 +94,7 @@
                 "os=Linux"
             ],
             "gclient_variables": {
+                "download_android_deps": false,
                 "run_fuchsia_emu": true
             },
             "gn": [
@@ -123,6 +131,9 @@
                 "device_type=none",
                 "os=Linux"
             ],
+            "gclient_variables": {
+                "download_android_deps": false
+            },
             "gn": [
                 "--fuchsia",
                 "--fuchsia-cpu",
@@ -162,6 +173,7 @@
                 "os=Linux"
             ],
             "gclient_variables": {
+                "download_android_deps": false,
                 "run_fuchsia_emu": true
             },
             "gn": [
@@ -198,6 +210,9 @@
                 "device_type=none",
                 "os=Linux"
             ],
+            "gclient_variables": {
+                "download_android_deps": false
+            },
             "gn": [
                 "--fuchsia",
                 "--fuchsia-cpu",
@@ -221,6 +236,7 @@
                 "os=Linux"
             ],
             "gclient_variables": {
+                "download_android_deps": false,
                 "run_fuchsia_emu": true
             },
             "gn": [
@@ -257,6 +273,10 @@
                 "device_type=none",
                 "os=Linux"
             ],
+            "gclient_variables": {
+                "download_android_deps": false,
+                "run_fuchsia_emu": true
+            },
             "gn": [
                 "--fuchsia",
                 "--fuchsia-cpu",
@@ -280,6 +300,7 @@
                 "os=Linux"
             ],
             "gclient_variables": {
+                "download_android_deps": false,
                 "run_fuchsia_emu": true
             },
             "gn": [
@@ -316,6 +337,10 @@
                 "device_type=none",
                 "os=Linux"
             ],
+            "gclient_variables": {
+                "download_android_deps": false,
+                "run_fuchsia_emu": true
+            },
             "gn": [
                 "--fuchsia",
                 "--fuchsia-cpu",
@@ -355,6 +380,7 @@
                 "os=Linux"
             ],
             "gclient_variables": {
+                "download_android_deps": false,
                 "run_fuchsia_emu": true
             },
             "gn": [