Use uint32_t for input source

The input source type originates from EventHub as an unsigned integer.
But later, it somehow becomes a signed value.
Even the InputListeners specify the source as uint32_t. To maintain the
consistency prior to adding new API that would again use source, convert
the source to uint32_t.
This also helps remove some static_casts, as well as ensures that the
order of input arguments is harder to confuse.

Bug: 134977432
Test: atest libinput_tests inputflinger_tests inputflinger_benchmarks
Change-Id: Iba10da08ee3a1004d50827785f570dab72a919d1
diff --git a/libs/input/tests/InputPublisherAndConsumer_test.cpp b/libs/input/tests/InputPublisherAndConsumer_test.cpp
index 1e51ea8..b002893 100644
--- a/libs/input/tests/InputPublisherAndConsumer_test.cpp
+++ b/libs/input/tests/InputPublisherAndConsumer_test.cpp
@@ -73,7 +73,7 @@
 
     constexpr uint32_t seq = 15;
     constexpr int32_t deviceId = 1;
-    constexpr int32_t source = AINPUT_SOURCE_KEYBOARD;
+    constexpr uint32_t source = AINPUT_SOURCE_KEYBOARD;
     constexpr int32_t displayId = ADISPLAY_ID_DEFAULT;
     constexpr std::array<uint8_t, 32> hmac = {31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21,
                                               20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10,
@@ -139,7 +139,7 @@
 
     constexpr uint32_t seq = 15;
     constexpr int32_t deviceId = 1;
-    constexpr int32_t source = AINPUT_SOURCE_TOUCHSCREEN;
+    constexpr uint32_t source = AINPUT_SOURCE_TOUCHSCREEN;
     constexpr int32_t displayId = ADISPLAY_ID_DEFAULT;
     constexpr std::array<uint8_t, 32> hmac = {0,  1,  2,  3,  4,  5,  6,  7,  8,  9,  10,
                                               11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21,